Datasets

Genome wide DNA methylation profiling of normal and HNSCC blood samples. The Illumina Infinium 450k Human DNA methylation Beadchip was used to obtain DNA methylation profiles across approximately 450,000 CpGs in serum samples. Samples included 12 cancer-free healthy controls, and 12 HNSCC cases.

Genome wide DNA methylation profiling of whole blood in schizophrenia patients and healthy subjects of different ages. The Illumina Infinium 450k Human DNA methylation Beadchip v1.2 was used to obtain DNA methylation profiles across approximately 480,000 CpGs. Dataset included 62 schizophrenia patients and 33 healthy subjects from Dutch descent.

Genome-wide DNA methylation level was studied to determine whether Rheumatoid arthritis patients (cases) has methylation differences comparing to normal controls in peripheral blood leukocytes (PBLs). We used Illumina HumanMethylation450 BeadChip array to determine the genome-wide DNA methylation difference in PBLs from Rheumatoid arthritis patients (cases) and normal controls

Background: As the most stable and experimentally accessible epigenetic mark, DNA methylation is of great interest to the research community. The landscape of DNA methylation across tissues, through development and in disease pathogenesis is not yet well characterised. Thus there is a need for rapid and cost effective methods for assessing genome-wide levels of DNA methylation. The Illumina Infinium HumanMethylation450 (450K) BeadChip is a very useful addition to the available methods but its complex design, incorporating two different assay methods, requires careful consideration. Accordingly, several normalization schemes have been published. We have taken advantage of known DNA methylation patterns associated with genomic imprinting and X-chromosome inactivation (XCI), in addition to the performance of SNP genotyping assays present on the array, to derive three independent metrics which we use to test alternative schemes of correction and normalization. These metrics also have potential utility as quality scores for datasets. Results: The standard index of DNA methylation at any specific CpG site is β = M/(M + U + 100) where M and U are methylated and unmethylated signal intensities. Betas calculated from raw signal intensities (the default GenomeStudio behaviour) perform well, but using 11 methylomic datasets we demonstrate that quantile normalization methods produce marked improvement, even in highly consistent data, by all three metrics. The commonly used procedure of normalizing betas is inferior to the separate normalization of M and U, and it is also advantageous to normalize Type I and Type II assays separately. More elaborate manipulation of quantiles proves to be counterproductive. Conclusions: Careful selection of preprocessing steps can minimise variance and thus improve statistical power, especially for the detection of the small absolute DNA methylation changes likely associated with complex disease phenotypes. For the convenience of the research community we have created an R software package called wateRmelon, compatible with the existing methylumi, minfi and IMA packages, that allows others to utilise the same normalization methods and data quality tests on 450K data.

Abstract The proper identification of differentially methylated CpGs is central in most epigenetic studies. The Illumina Human Methylation 450k BeadChip is widely used to quantify DNA methylation, nevertheless the design of an appropriate analysis pipeline faces severe challenges due to the convolution of biological and technical variability and the presence of a signal bias between Infinium I and II probe design types. Despite recent attempts to investigate how to analyze DNA methylation data with such an array design, it has not been possible to perform a comprehensive comparison between different bioinformatics pipelines due to the lack of appropriate datasets having both large sample size and sufficient number of technical replicates. Here we perform such a comparative analysis, targeting the problems of reducing the technical variability, eliminating the probe design bias and reducing the batch effect by exploiting two unpublished datasets, which included technical replicates and were profiled for DNA methylation either on peripheral blood, monocytes or muscle biopsies. The blood samples included individuals with Multiple Sclerosis (MS). We evaluated the performance of different analysis pipelines and demonstrated that a) it is critical to correct for the probe design type, since the amplitude of the measured methylation change depends on the underlying chemistry; b) the effect of different normalization schemes is mixed, and the most effective method in our hands were quantile normalization and Beta Mixture Quantile dilation (BMIQ); c) it is beneficial to correct for batch effects. In conclusion, our comparative analysis using a comprehensive dataset suggests an efficient pipeline for proper identification of differentially methylated CpGs using the Illumina 450k arrays.

Aging is a progressive process that results in the accumulation of intra- and extracellular alterations that in turn contribute to a reduction in health. Age-related changes in DNA methylation have been reported before and may be responsible for aging-induced changes in gene expression, although a causal relationship has yet to be shown. Using genome-wide assays, we analyzed age-induced changes in DNA methylation and their effect on gene expression with and without transient induction with the synthetic transcription modulating agent WY14,643. To demonstrate feasibility of the approach, we isolated peripheral blood mononucleated cells (PBMCs) from five young and five old healthy male volunteers and cultured them with or without WY14,643. Infinium 450K BeadChip and Affymetrix Human Gene 1.1 ST expression array analysis revealed significant differential methylation of at least 5 % (ΔYO > 5 %) at 10,625 CpG sites between young and old subjects, but only a subset of the associated genes were also differentially expressed. Age-related differential methylation of previously reported epigenetic biomarkers of aging including ELOVL2, FHL2, PENK, and KLF14 was confirmed in our study, but these genes did not display an age-related change in gene expression in PBMCs. Bioinformatic analysis revealed that differentially methylated genes that lack an age-related expression change predominantly represent genes involved in carcinogenesis and developmental processes, and expression of most of these genes were silenced in PBMCs. No changes in DNA methylation were found in genes displaying transiently induced changes in gene expression. In conclusion, aging-induced differential methylation often targets developmental genes and occurs mostly without change in gene expression.

DNA methylation is an epigenetic event whose pattern is altered frequently in a wide variety of human diseases. Smoking affects DNA methylation possibly leading to abnormal expression of a broad spectrum of genes which in turn may result to the various side effects and diseases associated with smoking. The long term effects of smoking have been widely studied but the mechanism(s) by which those effects may be reversible by smoking cessation are not clearly understood. Here, we conducted an epigenome-wide association study in peripheral-blood DNA in 464 individuals who were current, former and never-smokers. We identified 15 distinct loci (10 of which were novel) where DNA methylation was reduced in smokers and was reversed (but did not reach non-smoking levels) upon smoking cessation within 12 weeks. Although the functional impact of this reversal of DNA methylation is still not understood, this study illustrates the potential of epigenomics to provide insights into mechanisms of environmental and lifestyle exposures, and to suggest new avenues for clinical intervention

This Series contains data from 845 participants (188 men and 657 women) in the EPIC-Italy cohort that was produced at the Human Genetics Foundation (HuGeF) in Turin, Italy. At the last follow-up (2010), 424 participants remained cancer-free, 235 had developed primary breast cancer, 166 had developed primary colorectal cancer, and 20 had developed other primary cancers. Anthropometric measurements, and dietary and lifestyle information obtained by questionnaire are also available.

Down syndrome is characterized by a wide spectrum of clinical signs, which include cognitive and endocrine disorders and haematological abnormalities. Although it is well established that the causative defect of Down syndrome is the trisomy of chromosome 21, the molecular bases of Down syndrome phenotype are still largely unknown. We used the Infinium HumanMethylation450 BeadChip to investigate DNA methylation patterns in whole blood from 29 subjects affected by Down syndrome (DS), using their healthy relatives as controls (mothers and unaffected siblings). This family-based model allowed us to monitor possible confounding effects on DNA methylation patterns deriving from genetic and environmental (lifestyle) factors. The identified epigenetic signature of Down syndrome includes differentially methylated regions that, although enriched on chromosome 21, interest most of the other chromosomes and can be functionally linked to the developmental and haematological defects characteristic of the disease.

Progressive supranuclear palsy (PSP) and frontotemporal dementia (FTD) are two neurodegenerative diseases linked, at the pathologic and genetic level, to the macrutubule associated protein tau. We identified and replicated a dose-dependent effect of the risk-associated H1 haplotype on methylation levels within the region in independent datasets in blood and brain. These data reveal that the H1 haplotype increases risk for tauopathy via differential methylation, indicating a mediating role for methylation in dementia pathophysiology.

Genome wide DNA methylation profiles of whole blood from HIV positive men. The Illumina Infinium 450k Human DNA methylation Beadchip v1.2 was used to obtain DNA methylation profiles across approximately 480,000 CpGs. Dataset included 120 subjects from the USA but because of missing clinical characteristics only 109 subjects were used in the scientific publication. The study analyzed the effect of HIV viral load on host DNA methylation levels.

Genome wide DNA methylation profiles of whole blood from HIV positive men. The Illumina Infinium 450k Human DNA methylation Beadchip v1.2 was used to obtain DNA methylation profiles across approximately 480,000 CpGs. Dataset included 24 subjects from the USA. This data set was used as validation set for studying the effect of HIV viral load on host DNA methylation levels.

We developed a comprehensive analysis pipeline to conduct Epigenome-wide Association Studies (EWAS) using the Illumina Infinium HumanMethylation450 BeadChip, based on data from 2,664 individuals, and 36 samples measured in duplicate. We propose new approaches to quality control, data normalisation and batch correction through control-probe adjustment, and demonstrate that these improve data-quality. Using permutation testing we establish a null hypothesis for EWAS, show how it can be affected by correlation between individual methylation markers and present methods to restore statistical independence.

Human ageing affects the immune system resulting in an overall decline in immunocompetence. Although all immune cells are affected during aging, the functional capacity of T cells is most influenced and is linked to decreased responsiveness to infections and impaired differentiation. We studied age-related changes in DNA methylation and gene expression in CD4+ and CD8+ T cells from younger and older individuals. We observed marked difference between T cell subsets, with increased number of methylation changes and higher methylome variation in CD8+ T cells with age. The majority of age-related hypermethylated sites were located at CpG islands of silent genes and enriched for repressive histone marks. Specifically, in CD8+ T cell subset we identified strong inverse correlation between methylation and expression levels in genes associated with T cell mediated immune response (LGALS1, IFNG, CCL5, GZMH, CCR7, CD27 and CD248) and differentiation (SATB1, TCF7, BCL11B and RUNX3). Our results thus suggest the link between age-related epigenetic changes and impaired T cell function.

Alzheimer’s disease (AD) is a chronic neurodegenerative disorder that is characterized by progressive neuropathology and cognitive decline. We performed a cross-tissue analysis of methylomic variation in AD using samples from three independent human post-mortem brain cohorts. We identified a differentially methylated region in the ankyrin 1 (ANK1) gene that was associated with neuropathology in the entorhinal cortex, a primary site of AD manifestation. This region was confirmed as being substantially hypermethylated in two other cortical regions (superior temporal gyrus and prefrontal cortex), but not in the cerebellum, a region largely protected from neurodegeneration in AD, or whole blood obtained pre-mortem from the same individuals. Neuropathology-associated ANK1 hypermethylation was subsequently confirmed in cortical samples from three independent brain cohorts. This study represents, to the best of our knowledge, the first epigenome-wide association study of AD employing a sequential replication design across multiple tissues and highlights the power of this approach for identifying methylomic variation associated with complex disease.

Background: Epigenome-wide association studies (EWAS) using measurements of blood DNA methylation are performed to identify associations of methylation changes with environmental and lifestyle exposures, and with risk of developing disease. However, little is known about the variation of methylation markers in the population and their stability over time, both important factors in the design and interpretation of EWAS. Methods: We estimated the intraclass correlation coefficient (ICC) for each probe on the Illumina 450K methylation array in paired samples collected approximately six years apart from 92 participants in the Breakthrough Generations Study. We also evaluated relationships with age, reproductive and hormonal history, weight, alcohol intake and smoking. Results: Approximately 17% of probes on the 450K array had an ICC>0.50 and were considered stable variable methylated probes (stable-VMPs). Stable-VMPs were enriched for probes located in "shores" bordering CpG islands, and at approximately 1.3kb downstream from the transcription start site in the transition between the unmethylated promoter and methylated gene body. Both cross-sectional and longitudinal data analyses provided strong evidence for associations between changes in methylation levels and ageing. Smoking-related probes at 2q37.1 and AHRR were stable-VMPs and, as previously reported, related to time since quitting smoking. We also observed an excess of associations between methylation and weight changes beyond those expected by chance. Conclusion: Our results provide support for the use of WBC DNA methylation as a biomarker of exposure in EWAS. Larger studies, preferably with repeated measures over time, will be required to establish associations between specific probes and exposures.

DNA methylation has become increasingly recognized in the etiology of psychiatric disorders. Because brain tissue is not accessible in living humans, epigenetic studies are most often conducted in blood. Saliva is often collected for genotyping studies but is rarely used to examine DNA methylation because the proportion of epithelial cells and leukocytes varies extensively between individuals. The goal of this study was to evaluate whether saliva DNA is informative for studies of psychiatric disorders. Saliva and blood methylation was clearly distinguishable though there was positive correlation overall. There was little correlation in CpG sites within relevant candidate genes. Correlated CpG sites were more likely to occur in areas of low CpG density (i.e. CpG shores and open seas). There was more variability in CpG sites from saliva than blood, which may reflect its heterogeneity. Thus, this study provides a framework for using DNA methylation from saliva and suggests that DNA methylation of saliva may offer distinct opportunities for epidemiological and longitudinal studies of psychiatric traits.

Due to an increasingly aging population, the incidence of dementias such as Alzheimer’s disease are steadily rising, with recent estimates predicting >115million dementia sufferers by 2050. The ability to identify early markers in blood, which appear before the onset of clinical symptoms is of considerable interest to allow early intervention, particularly in “high risk” groups such as those with Type 2 Diabetes (T2D). Here we present longitudinal genome-wide DNA methylation data comparing 18 elderly individuals with T2D who developed pre-symptomatic dementia within an 18 month period following baseline assessment to 18 age, sex and education matched controls who maintained normal cognitive function. We identified a highly significant overlap in the effect size of the top-ranked methylation sites at baseline and follow-up, and identified 8 robust loci, some of which have been previously related to neurodegenerative processes, which were consistently differentially methylated prior to symptoms at baseline, and at 18 month follow up, when a diagnosis of pre-symptomatic dementia had been provided. Finally we show a significant overlap in the effect size of the top-ranked methylation sites in converters, only after they develop symptoms of pre-symptomatic dementia, with changes at the same loci in blood samples from patients with clinically-diagnosed Alzheimer’s disease.

Age-related changes in DNA methylation occurring in blood leukocytes during early childhood may reflect epigenetic maturation. We hypothesized that some of these changes involve gene networks of critical relevance in leukocyte biology and conducted a prospective study to elucidate the dynamics of DNA methylation. Serial blood samples were collected at 3, 6, 12, 24, 36, 48 and 60 months after birth in 10 healthy girls born in Finland and participating in the Type 1 Diabetes Prediction and Prevention Study. DNA methylation was measured using the HumanMethylation450 BeadChip. After filtering for the presence of polymorphisms and cell-lineage-specific signatures, 794 CpGs showed significant DNA methylation differences as a function of age in all children (41.5% age-methylated and 58.4% age-demethylated, bonferroni corrected p-value <0.001). Age-methylated CpGs were more frequently located in gene bodies and within +5 to +50 kilobases (kb) of transcription start sites (TSS), and enriched in developmental, neuronal and plasma membrane genes. Age-demethylated CpGs were associated to promoters and DNAse-I hypersensitivity sites, located within -5 to +5 kb of the nearest TSS, and enriched in genes related to immunity, antigen presentation, the polycomb-group protein complex and cytoplasm. This study reveals that susceptibility loci for complex inflammatory diseases (e.g. IRF5, NOD2, PTGER4) and genes encoding histone modifiers and chromatin remodeling factors (e.g. HDAC4, KDM2A, KDM2B, JARID2, ARID3A, SMARCD3) undergo DNA methylation changes in leukocytes during early childhood. These results open new perspectives to understand leukocyte maturation and provide a catalog of CpGs that may need to be corrected for age effects when performing DNA methylation studies in children.

Human DNA methylation Beadchip v1.2 was used to obtain n=113 Illumina DNA methylation array from whole blood samples. The main goal of the study was to measure the epigenetic age (also known as DNA methylation age) of subjects with a severe developmental disorder (known as syndrome X) and controls. To measure DNA methylation age, we used the epigenetic clock software described in Horvath S (n=2013) DNA methylation age of human tissues and cell types. Genome Biology.2013, 14:R115. DOI: 10.1186/10.1186/gb-2013-14-10-r115 PMID: 24138928.

Genome wide DNA methylation profiling of blood samples from eight female identical twins of Han Chinese for forensic age prediction, age 21 to 32. The Illumina Infinium HumanMethylation450 BeadChip was used to obtain DNA methylation profiles across approximately 485,000 CpGs at a single-nucleotide resolution. Samples included 8 pairs of identical female twins of Han Chinese.

We report that the DNA methylation profile of a child’s neonatal whole blood can be significantly influenced by his or her mother’s neonatal blood lead levels (BLL). We recruited 35 mother-infant pairs in Detroit and measured the whole blood lead (Pb) levels and DNA methylation levels at over 450,000 loci from current blood and neonatal blood from both the mother and the child. We found that mothers with high neonatal BLL correlate with altered DNA methylation at 564 loci in their children’s neonatal blood. Our results suggest that Pb exposure during pregnancy affects the DNA methylation status of the fetal germ cells, which leads to altered DNA methylation in grandchildren’s neonatal dried blood spots. This is the first demonstration that an environmental exposure in pregnant mothers can have an epigenetic effect on the DNA methylation pattern in the grandchildren.

Current therapy has turned HIV infection into a chronic condition. Clinically, some patients suffer prematurely from ailments associated with advanced age; however, the relationship between HIV and aging is unclear. Here we have collected a large cohort of HAART treated HIV+ subjects with both recent and chronic infection and recapitulated the shared phenotype of HIV and age. To further understand this signal, we applied validated models of DNA methylation-based biological age to establish a clear link between HIV infection and molecular age advancement. We then show this result to be robust to HIV duration, cellular composition, and general methylome disorder. Finally we show a pattern of hypomethylation in HIV+ individuals at the HLA locus. Together these results lead to a much-needed better understanding of the epigenetic consequences and gerontological aspects of chronic HIV infection.

Genome wide DNA methylation profiles of cerebellum from HIV positive and HIV negative human subjects. The Illumina Infinium 450k Human DNA methylation Beadchip v1.2 was used to obtain DNA methylation profiles across approximately 486,000 CpGs. Dataset included 92 subjects from the USA. The epigenetic clock software (Horvath 2013) was used to measure epigenetic age acceleration effects and to relate them to HIV status.

Changes in the DNA methylation (DNAm) landscape have been implicated in aging and cellular senescence. To unravel the role of specific DNAm patterns in late-life survival, we performed genome-wide methylation profiling in nonagenarians (n=111) and determined the performance of the methylomic predictors and conventional risk markers in a longitudinal setting. The survival model containing only the methylomic predictors was superior in terms of predictive accuracy compared with the models containing the conventional predictors body mass index and mini-mental state examination. At the 2.55-year follow-up, we identified 19 mortality-associated (false-discovery rate <0.5) CpG sites that mapped to genes functionally clustering around the nuclear factor kappa B (NF-κB) complex. Interestingly, none of the mortality-associated CpG sites overlapped with the established aging-associated DNAm sites. Our results are in line with previous findings on the role of NF-κB in controlling animal life spans and demonstrate the key role of this complex in human longevity.

We performed a genome-wide methylation study in whole-blood DNA from 404 ischemic stroke patient cohort, distributed across 3 ischemic stroke subtypes: Large-artery atherosclerosis (n=132), Small-artery disease (n=141) and Cardio embolic (n=127) . Illumina HumanMethylation450 BeadChip array was used to measure DNA methylation in CpG sites. We performed a genome-wide methylation study in whole-blood DNA from 185 ischemic stroke patient cohort. Illumina HumanMethylation450 BeadChip array was used to measure DNA methylation in CpG sites.

Background Chronological aging-associated changes in the human DNA methylome are studied by multiple epigenome-wide association studies (EWAS); however, the aging-associated DNAmet changes identified among different age groups and tissues vary and especially the rates of aging-associated alterations in the epigenome during adulthood remain unclear. Here, we further explore and characterize CpG-sites where DNA methylation levels alter at a constant rate during adulthood and are also independent of blood cell type heterogeneity. Results In the study, we observed 1,202 aging-associated CpG-sites (a-CpGs), of which 48% were hypermethylated with advancing age in whole blood with an especially narrow age range (40 - 49 years). Repeatedly reported a-CpGs in ELOVL2, FHL2, PENK and KLF14 were also identified. Regions with aging-associated hypermethylation were enriched to several gene ontology terms (especially on the cluster of developmental processes), while hypomethylated sites showed no enrichment. The genes with a higher number of a-CpG hits were more often hypermethylated. Of the 1,202 aging-associated CpG-sites in the present study, 987 were identified in previous study (Vitality 90+) as differentially methylated also between nonagenarians and young adults in a previous study, and importantly, the directions of changes were identical in the previous and in the present study. Conclusions The set of 987 replicated a-CpGs presented here are altered in strong association with chronological aging in the whole range of adulthood. Consequently, future studies should note the variability of the types of a-CpGs, and the a-CpGs presented here should be dissociated from the environmental-sensitive CpG-sites or from regions that are associated with aging in a non-linear manner due to the accumulation of senescence-related features. This report offers detailed and verified pool of a-CpGs in which DNAmet levels associate linearly with chronological age and of which are different from the non-linearly changing ones.

Childhood and cumulative exposure to trauma increases an individual's lifetime risk for psychiatric and stress-related disorders. This study evaluates DNA methylation in whole blood from African American participants, with the goal of identifying associaitons between peripheral DNA methylation and psychiatric symptoms.

Human DNA methylation Beadchip v1.2 was used to profile n=310 whole blood samples. The main goal of the study was to measure the epigenetic age (also known as DNA methylation age) of different ethnic groups. Here we focus on subjects older than 35. Groups include Tsimane Indians, Hispanics, and Caucasian samples. To measure DNA methylation age, we used the epigenetic clock software described in Horvath S (n=2013) DNA methylation age of human tissues and cell types. Genome Biology.2013, 14:R115. DOI: 10.1186/10.1186/gb-2013-14-10-r115 PMID: 24138928.

Human DNA methylation Beadchip v1.2 was used to profile 508 whole blood samples. The main goal of the study was to relate Parkinson's disease status to measures of epigenetic age acceleration based on DNA methylation data. Here we focus on Caucasian subjects. To measure DNA methylation age, we used the epigenetic clock software described in Horvath S (n=2013) DNA methylation age of human tissues and cell types. Genome Biology.2013, 14:R115. DOI: 10.1186/10.1186/gb-2013-14-10-r115 PMID: 24138928.

Human DNA methylation Beadchip v1.2 was used to profile n=335 whole blood samples. The main goal of the study was to measure the epigenetic age (also known as DNA methylation age) of Hispanics and Caucasians from the USA. To measure DNA methylation age, we used the epigenetic clock software described in Horvath S (n=2013) DNA methylation age of human tissues and cell types. Genome Biology.2013, 14:R115. DOI: 10.1186/10.1186/gb-2013-14-10-r115 PMID: 24138928.

Human DNA methylation Beadchip v1.2 was used to profile n=84 whole blood samples from Hispanics living in the USA. The main goal of the study was to relate Parkinson's disease status to measures of epigenetic age acceleration based on DNA methylation data. Here we focus on Hispanic subjects. To measure DNA methylation age, we used the epigenetic clock software described in Horvath S (n=2013) DNA methylation age of human tissues and cell types. Genome Biology.2013, 14:R115. DOI: 10.1186/10.1186/gb-2013-14-10-r115 PMID: 24138928.

Human DNA methylation Beadchip v1.2 was used to profile n=46 whole blood samples. The main goal of the study was to measure the epigenetic age (also known as DNA methylation age) of different ethnic groups. Here we focus on subjects younger than 35 years old. Groups include Tsimane Indians and Caucasian samples. To measure DNA methylation age, we used the epigenetic clock software described in Horvath S (n=2013) DNA methylation age of human tissues and cell types. Genome Biology.2013, 14:R115. DOI: 10.1186/10.1186/gb-2013-14-10-r115 PMID: 24138928.

Background: The mechanisms of how genetic variants (SNPs) identified in genome-wide association studies act to influence body mass remain unknown for most of these SNPs, which continue to puzzle the scientific community. Recent evidence points to epigenetic and chromatin state of the genome to have an important role. Methods: 355 healthy young individuals were genotyped for 52 known obesity-associated SNPs and we obtained DNA methylation levels in their blood using the Illumina 450K BeadChip. Associations between alleles and methylation at proximal cytosine residues were tested using a linear model adjusted for age, sex, weight category and a proxy for blood cell type counts. For replication in other tissues, we used two open-access datasets (skin fibroblasts, n=62; four brain regions, n=121-133) and an additional dataset in subcutaneous and visceral fat (n=149). Results: We found that alleles at 28 of these obesity-associated SNPs associate with methylation levels at 107 proximal CpG sites. Out of 107 CpG sites, 38 are located in gene promoters, including genes strongly implicated in obesity (MIR148A, BDNF, PTPMT1, NR1H3, MGAT1, SCGB3A1, HOXC12, PMAIP1, PSIP1, RPS10-NUDT3, RPS10, SKOR1, MAP2K5, SIX5, AGRN, IMMP1L, ELP4, ITIH4, SEMA3G, POMC, ADCY3, SSPN, LGR4, TUFM, MIR4721, SULT1A1, SULT1A2, APOBR, CLN3, SPNS1,SH2B1, ATXN2L, and IL27). Interestingly, the associated SNPs are in known eQTLs for some of these genes. We also found that the 107 CpGs are enriched in enhancers in peripheral blood mononuclear cells. Finally, our results indicate that some of these associations are not blood-specific as we successfully replicated four associations in skin fibroblasts. Conclusions: Our results strongly suggest that many obesity-associated SNPs are associated with proximal gene regulation, which was reflected by association of obesity risk allele genotypes with differential DNA methylation. This study highlights the importance of DNA methylation and other chromatin marks as a way to understand the molecular basis of genetic variants associated to human diseases and traits.

Folate, and its synthetic form folic acid, function as donor of one-carbon units and have been, together with other B-vitamins, implicated in programming of epigenetic processes such as DNA methylation during early development. To what extent regulation of DNA methylation can be altered via B-vitamins later in life, and how this relates to health and disease, is not exactly known. The aim of this study was to identify effects of long-term supplementation with folic acid and vitamin B12 on genome-wide DNA methylation in elderly subjects. This project was part of a randomized, placebo-controlled trial on effects of supplemental intake of folic acid and vitamin B12 on bone fracture incidence (B-PROOF study). Participants with mildly elevated homocysteine levels, aged 65-75 years, were randomly assigned to take 400 µg folic acid and 500 µg vitamin B12 per day or a placebo during an intervention period of two years. DNA was isolated from buffy coats, collected before and after intervention, and genome-wide DNA methylation was determined in 87 participants (n=44 folic acid/vitamin B12, n=43 placebo) using the Infinium HumanMethylation450 BeadChip. After intervention with folic acid and vitamin B12, 162 (versus 14 in the placebo group) of the 431,312 positions were differentially methylated as compared to baseline. Comparisons of the DNA methylation changes in the participants receiving folic acid and vitamin B12 versus placebo, revealed one single differentially methylated position (cg19380919) with a borderline statistical significance. However, based on the analyses of differentially methylated regions (DMRs) consisting of multiple positions, we identified 6 regions that differed statistically significantly between the intervention and placebo group. Pronounced changes were found for regions in the DIRAS3, ARMC8 and NODAL genes, implicated in carcinogenesis and early embryonic development. Furthermore, serum levels of folate and vitamin B12 or plasma homocysteine were related to DNA methylation of 173, 425 and 11 regions, respectively. Interestingly, for several members of the developmental HOX genes, DNA methylation was related to serum levels of folate. Long-term supplementation with folic acid and vitamin B12 in elderly subjects resulted in effects on DNA methylation of several genes, among which genes implicated in developmental processes.

The maternal and paternal copies of the genome are both required for mammalian development and this is primarily due to imprinted genes, those that are mono-allelically expressed based on parent-of-origin. Typically, this pattern of expression is regulated by differentially methylated regions (DMRs) that are established in the germline and maintained after fertilisation. There are a large number of germline DMRs that have not yet been associated with imprinting and their function in development is unknown. In this study, we developed a genome-wide approach to identify novel imprinted DMRs, specifically in the human placenta, and investigated the dynamics of imprinted DMRs during development in somatic and extra-embryonic tissues. DNA methylation was evaluated using the Illumina HumanMethylation450 array in 116 human tissue samples, publically available reduced representation bisulfite sequencing in the human embryo and germ cells, and targeted bisulfite sequencing in term placentas. 43 known and 101 novel imprinted DMRs were identified in the human placenta, by comparing methylation between diandric and digynic triploids and female and male gametes. 72 novel DMRs showed a pattern consistent with placental-specific imprinting and this mono-allelic methylation was entirely maternal in origin. Strikingly, these DMRs exhibited polymorphic imprinted methylation specifically in placenta. These data suggest that imprinting in human development is far more extensive and dynamic than previously reported and that the placenta preferentially maintains maternal germline-derived DNA methylation

Genome-wide analysis of DNA methylation profiles from patients with Sjögren's syndrome with high versus low fatigue levels using the Illumina Infinium HumanMethylation450 Beadchip array. Background Chronic fatigue is a common, disabling, and poorly understood phenomenon. Recent studies indicate that epigenetic mechanisms may be involved in the expression of fatigue, a prominent feature of primary Sjögren’s syndrome (pSS). The aim of this study was to investigate whether DNA methylation profiles of whole blood are associated with fatigue in patients with pSS. Methods 48 pSS patients with high (n=24) or low (n=24) fatigue as measured by a visual analogue scale were included. Genome-wide DNA methylation was investigated using the Illumina HumanMethylation450 BeadChip array.

DNA-methylation profiling of Whole blood genomic DNAs collected at EDIC baseline and monocytes at EDIC years 16/17 years from participants of Diabetes Control and Complications Trial/ Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study This SuperSeries is composed of the SubSeries listed below.

Objective: Cocaine use disorders (CUD) represent a major public health problem in many countries. To better understand the interaction between the environmental modulations and phenotype, the aim of the present study was to investigate the DNA methylation pattern of CUD patients, which were concomitant dependents of cocaine and crack, and healthy controls. Methods: We studied DNA methylation profiles in the peripheral blood of 23 CUD patients and 24 healthy control subjects using the Illumina Infinium HumanMethylation450 BeadChip arrays. Results: Comparison between CUD patients and controls revealed 186 differentially methylated positions (DMPs, adjP<10-5) related to 152 genes, with a subset of CpGs confirmed by pyrosequencing. DNA methylation patterns discriminated CUD patients and control groups. A gene network approach showed that EHMT1, EHMT2, MAPK1, MAPK3, MAP2K1 and HDAC5 genes, which are involved in transcription and chromatin regulation cellular signaling pathways, were also associated with cocaine dependence. Conclusion: The investigation of DNA methylation patterns in CUD patients may contribute to a better understanding of the biological mechanisms involved in cocaine use disorders.

DNA methylation likely plays a role in the regulation of human stress reactivity. In a genome-wide analysis of blood DNA methylation in 85 healthy individuals a locus in the Kit ligand (KITLG) gene (cg27512205) had the strongest association with cortisol stress reactivity (p=5.8x10-6). Replication was obtained in two independent samples, one using blood (N=45, p=0.001) and the other using buccal cells (N=255,p=0.004). KITLG methylation strongly mediated the relationship between childhood trauma and cortisol stress reactivity (32% mediation). Its genomic location (CpG island shore within an H3K27ac enhancer mark) provide further evidence that KITLG methylation is functionally relevant for the programming of stress reactivity. Our results extend preclinical evidence for epigenetic regulation of stress reactivity to humans and provide leads to enhance our understanding of the neurobiological pathways underlying stress vulnerability.

Although it is assumed that epigenetic mechanisms, such as changes in DNA methylation (DNAm), underlie the relationship between adverse intrauterine conditions and adult metabolic health, evidence from human studies remains scarce. Therefore, we evaluated whether DNAm in whole blood mediated the association between prenatal famine exposure and metabolic health in 422 individuals exposed to famine in utero and 463 (sibling) controls. We implemented a two-step analysis, namely, a genome-wide exploration across 342,596 cytosine-phosphate-guanine dinucleotides (CpGs) for potential mediators of the association between prenatal famine exposure and adult body mass index (BMI), serum triglycerides (TG), or glucose concentrations, which was followed by formal mediation analysis. DNAm mediated the association of prenatal famine exposure with adult BMI and TG but not with glucose. DNAm at PIM3 (cg09349128), a gene involved in energy metabolism, mediated 13.4% [95% confidence interval (CI), 5 to 28%] of the association between famine exposure and BMI. DNAm at six CpGs, including TXNIP (cg19693031), influencing β cell function, and ABCG1 (cg07397296), affecting lipid metabolism, together mediated 80% (95% CI, 38.5 to 100%) of the association between famine exposure and TG. Analyses restricted to those exposed to famine during early gestation identified additional CpGs mediating the relationship with TG near PFKFB3 (glycolysis) and METTL8 (adipogenesis). DNAm at the CpGs involved was associated with gene expression in an external data set and correlated with DNAm levels in fat depots in additional postmortem data. Our data are consistent with the hypothesis that epigenetic mechanisms mediate the influence of transient adverse environmental factors in early life on long-term metabolic health. The specific mechanism awaits elucidation.

Genome-wide DNA methylation profiling was performed in Dutch men consuming eel from relatively low- or high-polluted areas, resulting in a broad range of serum POP levels. The Illumina Infinium 450K Human DNA methylation Beadchip v1.0HD was used to measure DNA methylation in these men and associate this with serum levels of persistent organic pollutants (POPs). In total 48 POPs were measured, of which 30 POPs had levels above the detection limit in at least 60% of the participants. Furthermore, 11 different clinical parameters were measured as biomarkers for health. The leukocyte count was measured in each sample to adjust DNA methylation values. Furthermore, participants reported possible confounders in a questionnaire.

Longitudinal samples were collected from neonates in the NICU at the Royal Women’s Hospital in Melbourne, Australia. Blood collection occurred by heel stick and was collected on Whatman paper shortly after birth at 25 weeks gestation, one day post birth, and at the equivalent of 28, 32, 36, and 40 weeks gestation.

Background: Schizophrenia is a severe, highly heritable, neuropsychiatric disorder characterized by episodic psychosis and altered cognitive function. Despite success in identifying genetic variants associated with schizophrenia, there remains uncertainty about the causal genes involved in disease pathogenesis and how their function is regulated. Insights into the functional complexity of the genome have focussed attention on the role of non-sequence-based genomic variation in health and disease. Although a better understanding of the molecular mechanisms underlying disease phenotypes is best achieved using an integrated functional genomics strategy, few studies have attempted to systematically integrate genetic and epigenetic epidemiological approaches. Results: We performed a multi-stage epigenome-wide association study (EWAS), quantifying genome-wide patterns of DNA methylation in a total of 1,801 individuals from three independent sample cohorts. We identified multiple differentially methylated positions (DMPs) and region (DMRs) associated with schizophrenia, independently of important confounders such as smoking, with consistent effects across the three independent cohorts. We also show that polygenic burden for schizophrenia is associated with epigenetic variation at multiple loci across the genome, independently of loci implicated in the analysis of diagnosed schizophrenia. Finally, we show how DNA methylation quantitative trait loci (mQTL) analyses can be used to annotate the extended genomic regions nominated by genetic studies of schizophrenia, with Bayesian co-localization analyses highlighting potential regulatory variation causally involved in disease. Conclusion: This study represents the first systematic integrated analysis of genetic and epigenetic variation in schizophrenia, introducing a methodological pipeline that can be used to inform EWAS analyses of other complex traits and diseases. We demonstrate the utility of using polygenic risk score (PRS) for identifying molecular variation associated with etiological variation, and mQTLs for refining the functional/regulatory variation associated with schizophrenia risk variants. Finally, we present strong evidence for the co-localization of genetic associations for schizophrenia and differential DNA methylation.

Genome wide DNA methylation profiling of female Crohn's disease patients versus healthy female controls. The Illumina Infinium 450k Human DNA methylation Beadchip was used to obtain DNA methylation profiles across approximately 485,000 CpGs in peripheral blood samples. Samples included 25 healthy controls and 18 female patients with histologically confirmed CD.

Background: Early life epigenetic programming influences adult health outcomes. Moreover, DNA methylation levels have been found to change more rapidly during the first years of life. Our aim was the identification and characterization of the CpG sites that are modified with time during the first years of life. We hypothesize that these DNA methylation changes would lead to the detection of genes that might be epigenetically modulated by environmental factors during early childhood and which, if disturbed, might contribute to susceptibility to diseases later in life. Methods: The study of the DNA methylation pattern of 485577 CpG sites was performed on 30 blood samples from 15 subjects, collected both at birth and at 5 years old, using Illumina® Infinium 450 k array. To identify differentially methylated CpG (dmCpG) sites, the methylation status of each probe was examined using linear models and the Empirical Bayes Moderated t test implemented in the limma package of R/Bioconductor. Surogate variable analysis was used to account for batch effects. Results: DNA methylation levels significantly changed from birth to 5 years of age in 6641 CpG sites. Of these, 36.79 % were hypermethylated and were associated with genes related mainly to developmental ontology terms, while 63.21 % were hypomethylated probes and associated with genes related to immune function. Conclusions: Our results suggest that DNA methylation alterations with age during the first years of life might play a significant role in development and the regulation of leukocyte-specific functions. This supports the idea that blood leukocytes experience genome remodeling related to their interaction with environmental factors, underlining the importance of environmental exposures during the first years of life and suggesting that new strategies should be take into consideration for disease prevention.

Abstract Background: Schizophrenia is a severe, highly heritable, neuropsychiatric disorder characterized by episodic psychosis and altered cognitive function. Despite success in identifying genetic variants associated with schizophrenia, there remains uncertainty about the causal genes involved in disease pathogenesis and how their function is regulated. Insights into the functional complexity of the genome have focussed attention on the role of non-sequence-based genomic variation in health and disease. Although a better understanding of the molecular mechanisms underlying disease phenotypes is best achieved using an integrated functional genomics strategy, few studies have attempted to systematically integrate genetic and epigenetic epidemiological approaches. Results: We performed a multi-stage epigenome-wide association study (EWAS), quantifying genome-wide patterns of DNA methylation in a total of 1,801 individuals from three independent sample cohorts. We identified multiple differentially methylated positions (DMPs) and region (DMRs) associated with schizophrenia, independently of important confounders such as smoking, with consistent effects across the three independent cohorts. We also show that polygenic burden for schizophrenia is associated with epigenetic variation at multiple loci across the genome, independently of loci implicated in the analysis of diagnosed schizophrenia. Finally, we show how DNA methylation quantitative trait loci (mQTL) analyses can be used to annotate the extended genomic regions nominated by genetic studies of schizophrenia, with Bayesian co-localization analyses highlighting potential regulatory variation causally involved in disease. Conclusion: This study represents the first systematic integrated analysis of genetic and epigenetic variation in schizophrenia, introducing a methodological pipeline that can be used to inform EWAS analyses of other complex traits and diseases. We demonstrate the utility of using polygenic risk score (PRS) for identifying molecular variation associated with etiological variation, and mQTLs for refining the functional/regulatory variation associated with schizophrenia risk variants. Finally, we present strong evidence for the co-localization of genetic associations for schizophrenia and differential DNA methylation.

Genome wise DNA methylation profiling of peripheral blood mononuclear cells (PBMCs) obtained from younger sedentary (Y-SED), older sedentary (O-SED) and older aerobically exercise trained (O-Ex) human subjects. The Illumina 450K methylation beadchip array was used to obtain DNA methylation profiles across approximately 450,000 CpG dinucleotide methylation loci in DNA isolated from PBMCs. Samples include 12 Y-SED subjects, 15 O-SED subjects and 11 O-Ex subjects.

FM is a complex syndrome with physiological, genetics and environmental factors involved. It can present changes in functional neuroimaging, in cortical excitability measurements performed by transcranial magnetic stimulation and in grey matter density. Similarly, it has been shown that patients with FM have abnormal autonomic control, inflammatory profile and dysfunctional hypothalamic–pituitary–adrenal axis leading to disruptive sleep and fatigue. We characterized clinical and neurophysiological parameters and peripheral blood DNA methylation profiles of patients with FM and compared them to sex and age matched healthy controls. We hypothesized that these exploratory analyses could provide mechanistic insights into the pathophysiology of FM and possibly contribute to the future development of biological markers of diagnosis.We showed that patients with fibromyalgia have different (mainly hypo-) methylated CpG sites related to genes implicated in immune system and response to external stress pathways and that this methylation profile is related to a dysfunctional connectivity in pain network, adding evidence to consider fibromyalgia as a DOHAD disorder.

DNA methylation plays an important role in development of disease and the process of aging. In this study we examine DNA methylation at 476,366 sites throughout the genome of white blood cells from a population cohort (N = 421) ranging in age from 14 to 94 years old. Age affects DNA methylation at almost one third (29%) of the sites (Bonferroni adjusted P-value <0.05), of which 60.5% becomes hypomethylated and 39.5% hypermethylated with increasing age. DNA methylation sites that are located within CpG islands (CGIs) more often become hypermethylated compared to sites outside an island. CpG sites in promoters are more unaffected by age, whereas sites in enhancers more often becomes hypo- or hypermethylated. Hypermethylated sites are overrepresented among genes that are involved in DNA binding, transcription regulation, processes of anatomical structure and developmental process and cortex neuron differentiation (P-value down to P = 9.14*10−67). By contrast, hypomethylated sites are not strongly overrepresented among any biological function or process. Our results indicate that the 23% of the variation in DNA methylation is attributed chronological age, and that hypermethylation is more site-specific than hypomethylation. It appears that the change in DNA methylation partly overlap with regions that change histone modifications with age, indicating an interaction between the two major epigenetic mechanisms. Epigenetic modifications and change in gene expression over time most likely reflects the natural process of aging and variation between individuals might contribute to the development of age-related phenotypes and diseases such as type II diabetes, autoimmune and cardiovascular disease.

Genome wide DNA methylation profiling with the HumanMethylation450 BeadChip (450k) of peripheral blood samples of 46 adult female monozygotic twin-pairs obtained at the same time point. Samples included 41 healthy females (not diagnosed with cancer to date) paired with their co-twin diagnosed with cancer within a 5 year window around the time of sampling as well as 5 extra pairs with a co-twin diagnosed with cancer within 11 to 5 years prior to blood sampling.

Tissue differences are one of the largest contributors to variability in the human DNA methylome. Despite the tissue specific nature of DNA methylation, the inaccessibility of human brain samples necessitates the frequent use of surrogate tissues such as blood, in studies of associations between DNA methylation and brain function and health. Results from studies of surrogate tissues in humans are difficult to interpret in this context, as the connection between blood-brain DNA methylation is tenuous and not well documented. Here we aimed to provide a resource to the community to aid interpretation of blood based DNA methylation results in the context of brain tissue. We used paired samples from 16 individuals from three brain regions and whole blood, run on the Illumina 450K Human Methylation Array to quantify the concordance of DNA methylation between tissues. From these data we have made available metrics on: the variability of CpGs in our blood and brain samples, the concordance of CpGs between blood and brain, and estimations of how strongly a CpG is affected by cell composition in both blood and brain through the web application BECon (Blood-Brain Epigenetic Concordance; https://redgar598.shinyapps.io/BECon/). We anticipate that BECon will enable biological interpretation of blood based human DNA methylation results, in the context of brain.

Epienome-wide DNA methylation profiling of systemic lupus erythematosus (SLE). The Illumina HumanMethylation450K Beadchip was used to obtain DNA methylation profiles across approximately 450,000 CpGs in normal human blood samples from females. Samples included 33 non-SLE female patients (control) and 57 SLE female patients. SLE patients:- Ethnicity included 39 African americans and 18 European Americans. SLEDAI score ranged from 2-30. Non-SLE pateients:-Ethnicity indclued 17 African Americans and 16 European Americans, all with a SLEDAI score of zero.

Epigenetic dysregulation has emerged as mechanism in the etiology of neurodevelopmental disorders. Two such disorders, CHARGE and Kabuki syndromes, result from loss of function mutations in chromodomain helicase DNA-binding protein 7 (CHD7LOF) and lysine (K) methyltransferase 2D (KMT2DLOF), respectively. We expected that epigenetically driven developmental pathways regulated by CHD7 and KMT2D would overlap and that DNA methylation (DNAm) alterations downstream of the mutations in these genes would identify common target genes, elucidating a mechanistic link between these conditions, as well as specific target genes for each. Genome-wide DNAm profiles in individuals with CHARGE and Kabuki syndromes with CHD7LOF or KMT2DLOF identified distinct sets of DNAm differences in each of the disorders, which were used to generate two unique, highly specific and sensitive DNAm signatures. These DNAm signatures were able to differentiate pathogenic mutations in these two genes from controls and from each other. Analysis of each gene-specific DNAm signature identified common gene targets which could account for some of the clinical overlap in these syndromes, as well as distinct gene targets. Our findings demonstrate how characterization of the epigenome can contribute to our understanding of disease pathophysiology for epigenetic disorders, paving the way for explorations of novel therapeutics.

Osteoporosis is an age-related metabolic bone disease. Hence, osteoporotic patients might suffer from molecular features of accelerated aging, which is generally reflected by specific age-associated DNA methylation (DNAm) changes. In this study, we analyzed genome wide DNAm profiles of peripheral blood from patients with manifest primary osteoporosis and non-osteoporotic controls. Statistical analysis did not reveal any individual CG dinucleotides (CpG sites) with significant aberrant DNAm in osteoporosis. Subsequently, we analyzed if age-associated DNAm patterns are increased in OP. Using three independent age-predictors we did not find any evidence for accelerated epigenetic age in blood of osteoporotic patients. Taken together, osteoporosis is not reflected by characteristic DNAm patterns of peripheral blood that might be used as biomarker for the disease. The prevalence of osteoporosis is age-associated – but it is not associated with premature epigenetic aging in peripheral blood.

Epigenetic and genetic profiles (N=67) were based on the Illumina Infinium HumanMethylation450 BeadChip. We searched for differentially methylated probes (DMPs) and regions (DMRs). For genetic associations we analyzed the CpG-SNPs present on the array

Genome wide DNA methylation profiling of IDU+/HCV+ and IDV-/HCV- individuals for DNA samples extracted from peripheral blood. The Illumina Infinium Human DNA methylation 450 Beadchip was used to obtain DNA methylation profiles across approximately 480,000 CpGs. Samples included 216 IDU+/HCV+ and 170 IDU-/HCV- individuals. The goal was to identify genome-wide differentially methylated CpG sites between IDU+/HCV+ and IDU-/HCV- samples.

Epigenetic alterations may represent new therapeutic targets and/or biomarkers of allergic rhinitis (AR). Our aim was to examine genome-wide epigenetic changes induced by controlled pollen exposure in the Environmental Exposure Unit (EEU). 38 AR-sufferers and 8 non-allergic controls were exposed to grass pollen for 3h on two consecutive days. We interrogated DNA methylation at baseline and 3h in peripheral blood mononuclear cells (PBMCs) using the Infinium Methylation 450K array. We corrected for demographics, cell composition, and multiple testing (Benjamini-Hochberg), and verified hits using bisulfite PCR-pyrosequencing and qPCR. To extend these findings to a clinically relevant tissue, we investigated DNA methylation and gene expression of mucin 4 (MUC4), in nasal brushings from a separate validation cohort exposed to birch pollen. In PBMCs of allergic rhinitis participants, 42 sites showed significant DNA methylation changes of 2% or greater. DNA methylation changes in tryptase gamma 1 (TPSG1), schlafen 12 (SLFN12) and MUC4 in response to exposure were validated by pyrosequencing. SLFN12 DNA methylation significantly correlated with symptoms (p<0.05), and baseline DNA methylation pattern was found to be predictive of symptom severity upon grass allergen exposure (p<0.05). Changes in MUC4 DNA methylation in nasal brushings in the validation cohort correlated with drop in peak nasal inspiratory flow (Spearman r = 0.314, p = 0.034), and MUC4 gene expression was significantly increased (p<0.0001). This study revealed novel and rapid epigenetic changes upon exposure in a controlled allergen challenge facility, identified baseline epigenetic status as a predictor of symptom severity.

Intrauterine exposure to hyperglycemic environment is reported to confer increased metabolic risk in later life, supporting the “developmental origins of health and disease” hypothesis. Epigenetic alterations are suggested as one of the possible underlying mechanisms. We measured DNA methylation using Infinium HumanMethylation450 BeadChip in siblings discordant for maternal gestational diabetes mellitus (GDM), which may allow possible genetic and environmental confounding effects to be reduced. Of the 465,447 CpG sites analyzed, 12 showed differential methylation (false discovery rate < 0.15), including markers within genes associated with monogenic diabetes (HNF4A) or obesity (RREB1). The overall methylation at the HNF4A gene region showed inverse correlations with mRNA expression levels though non-significant. In a gene set enrichment analysis, differentially methylated CpGs-associated genes were involved in metabolism and signal transduction pathways. Our findings implicate epigenetic mechanisms in relation to prenatal exposure to maternal hyperglycemia.

Cord blood DNA methylation is associated with numerous health outcomes and environmental exposures. Whole cord blood DNA reflects all nucleated blood cell types, while centrifuging whole blood separates red blood cells by generating a white blood cell buffy coat. Both sample types are used in DNA methylation studies. Cell types have unique methylation patterns and processing can impact cell distributions, which may influence comparability. To evaluate differences in cell composition and DNA methylation between buffy coat and whole cord blood samples, cord blood DNA methylation was measured with the Infinium EPIC BeadChip (Illumina) in 8 individuals, each contributing buffy coat and whole blood samples.

There is increasing evidence that metabolic diseases originate in early life, and epigenetic changes have been implicated as key drivers of this early life programming. This led to the hypothesis that epigenetic marks present at birth may predict an individual’s future risk of obesity and type 2 diabetes. In this study, we assessed whether epigenetic marks in blood of newborn children were associated with BMI and insulin sensitivity later in childhood. DNA methylation was measured in neonatal blood spot samples of 439 children using the Illumina Infinium 450k BeadChip. Associations were assessed between DNA methylation at birth and BMI z-scores, body fat mass, fasting plasma glucose, insulin and HOMA-IR at age 5 years, as well as birthweight, maternal BMI and smoking status. No individual methylation sites at birth were associated with obesity or insulin sensitivity measures at 5 years. DNA methylation in 69 genomic regions at birth was associated with BMI z-scores at age 5 years, and in 63 regions with HOMA-IR. The methylation changes were generally small (<5%), except for a region near the non-coding RNA nc886 (VTRNA2-1) where a clear link between methylation status at birth and BMI in childhood was observed (P=0.001). Associations were also found between DNA methylation, maternal smoking, and birth weight. We identified a number of DNA methylation regions at birth that were associated with obesity or insulin sensitivity measurements in childhood. These findings support the mounting evidence on the role of epigenetics in programming of metabolic health. Whether many of these small changes in DNA methylation are causally related to the health outcomes, and of clinical relevance, remains to be determined, but the nc886 region represents a promising obesity risk marker that warrants further investigation.

The growing obesity “epidemic” has shed light on its negative impact on overall health status, not only in relation to cardiovascular disorders and metabolic syndrome, but also in regard to its influence on a variety of other health conditions, including autoimmune diseases, such as Multiple Sclerosis (MS). High Body Mass index (BMI) is a risk factor for MS, however, it is not known whether and how it could impact disease course. Several studies, including those on the Dutch Famine, have highlighted the role of epigenetic modifications in mediating phenotypic changes in response to metabolic shifts, suggesting that epigenetic changes could be a potential mechanism for BMI-driven differences in disease course. Using the Illumina 450K array, we identified genome-wide differences in DNA methylation between blood monocytes from therapy-naïve RRMS patients with high BMI compared to low BMI. Differences were subtle, however, were heavily skewed in the positive direction in the high BMI group, indicative of overall DNA hypermethylation. Further curation of differentially methylated genes, using stringent criteria, revealed enrichment in anti-inflammatory functions among the top hypermethylated genes. Thus, epigenomic changes related to inflammatory processes of monocytes are detected in MS patients with high BMI compared to those with low BMI and could potentially impact disease course by modulating immune-driven neurotoxicity.

Methylome-wide DNA methylation profiling of whole blood samples in health children to find age-associated methylation sites. The Illumina Infinium 450k Human DNA methylation Beadchip v1.2 was used to obtain DNA methylation profiles across approximately 485,000 CpGs in 48 samples. Samples included 29 boys and 19girls.

Genome-wide patterns of DNA methylation were quantified using the Illumina Infinium HumanMethylation450 BeadChip (“450K array”) in DNA samples isolated from whole blood collected at age 18 from members of the Environmental Risk (E-Risk) Longitudinal Twin Study.

Genome-wide DNA methylation level was studied to determine whether multiple sclerosis patients (cases) has methylation differences comparing to normal controls in PBLs. We used Illumina HumanMethylation450 BeadChip array to determine the genome-wide DNA methylation difference in peripheral blood from multiple sclerosis patients (cases) and normal controls

This dataset is used as replication set for Illumina 450k. Genome wide DNA methylation profiling of IDU+/HCV+ and IDV-/HCV- individuals for DNA samples extracted from peripheral blood. The Illumina Infinium Human DNA methylation 450 Beadchip was used to obtain DNA methylation profiles across approximately 480,000 CpGs. Samples included 216 IDU+/HCV+ and 170 IDU-/HCV- individuals. The goal was to identify genome-wide differentially methylated CpG sites between IDU+/HCV+ and IDU-/HCV- samples.

Genome-wide Illumina InfiniumMethylation 450 K DNA methylation analysis was performed on blood samples from clinical atherosclerosis patients (n = 8) and healthy donors (n = 8) in the LVAD study (NCT02174133, NCT01799005). Multiple differentially methylated regions (DMR) could be identified in atherosclerosis patients, related to epigenetic control of cell adhesion, chemotaxis, cytoskeletal reorganisations, cell proliferation, cell death, estrogen receptor pathways and phagocytic immune responses. Furthermore, a subset of 34 DMRs related to impaired oxidative stress, DNA repair, and inflammatory pathways could be replicated in an independent cohort study of donor-matched healthy and atherosclerotic human aorta tissue (n = 15) and human carotid plaque samples (n = 19). Upon integrated network analysis, BRCA1 and CRISP2 DMRs were identified as most central disease-associated DNA methylation biomarkers. Differentially methylated BRCA1 and CRISP2 regions were verified by MassARRAY Epityper and pyrosequencing assays and could be further replicated in blood, aorta tissue and carotid plaque material of atherosclerosis patients. Moreover, methylation changes at BRCA1 and CRISP2 specific CpG sites were consistently associated with subclinical atherosclerosis measures (coronary calcium score and carotid intima media thickness) in an independent sample cohort of middle-aged men with subclinical cardiovascular disease in the Aragon Workers' Health Study (n = 24). Altogether, BRCA1 and CRISP2 DMRs hold promise as novel blood surrogate markers for early risk stratification and CVD prevention.

Congenital hypopituitarism (CH) is chracterized with one or more hormones secreted deficiency by the pituitary gland, which leads to metabolic disorders, amenorrhea and infertility of the patients; however, the involved molecular mechanisms has not yet fully elucidated. We examined genome-wide methylation levels of whole blood DNA in 12 CH patients and 12 age-matched controls using Illumina HumanMethylation450 array. Significantly different methylated loci were further validated in another 40 patients and 40 controls with quantitative bisulfite pyrosequencing method.

Differential DNA methylation (DNAm) in the brain is associated with many psychiatric diseases, but access to brain tissues is essentially limited to post-mortem samples. The use of surrogate tissues has become common in identifying methylation changes associated with psychiatric disease. In this study, we determined the extent to which peripheral tissues can be used as surrogates for DNAm in the brain. Blood, saliva, buccal, and live brain tissue samples from 27 medically intractable epilepsy patients undergoing brain resection were collected. Genome-wide methylation was assessed with the Infinium HumanMethylation450 (n=12) and HumanMethylationEPIC BeadChip arrays (n=21). For each CpG and each gene, levels of brain-peripheral tissue correlation varied widely. This indicates that to determine the most useful surrogate tissue for representing brain DNAm, the patterns specific to the genomic region of interest must be considered. To assist in that objective, we have developed a website, IMAGE-CpG, that allows researchers to interrogate DNAm levels and degree of cross-tissue correlation in user-defined locations across the genome.

Genome wide DNA methylation profiling of whole blood and saliva samples in Parkinson's disease (PD) patients and PD-free controls. The Illumina Infinium 450k Human DNA methylation Beadchip was used to obtain DNA methylation profiles. Samples included 335 PD patients and 237 controls with blood DNA.

Crohn’s disease is a relapsing inflammatory disorder with a variable clinical course. While most patients present with purely an inflammatory phenotype (B1) at diagnosis, a subgroup (~20%) rapidly progresses to complicated disease manifestations that include stricturing (B2) within 5 years. DNA methylation is a key epigenetic mechanism that can regulate gene expression and thereby influence the development and progression of complex diseases. Site-specific DNA methylation differences have been reported in peripheral blood of patients with Crohn’s disease, but investigation of the temporal relationship between methylation and disease is required to establish whether the methylome plays a causal role and can be leveraged for therapeutic benefits. To this end, we conducted an epigenome-wide study of methylation (~850K sites) in peripheral blood at diagnosis and during follow-up from the RISK pediatric Crohn’s disease inception cohort. While some methylation changes associated with Crohn’s disease might be causal, in peripheral blood the vast majority are found to be a transient consequence of inflammation and thus a symptom of disease.

Depression is a common and disabling disorder, representing a major social and economic health issue. Moreover, depression is associated with the progression of diseases with an inflammatory etiology including many inflammatory-related disorders. At the molecular level, the mechanisms by which depression might promote the onset of these diseases and associated immune-dysfunction are not well understood. In this study we assessed genome-wide patterns of DNA methylation in whole blood-derived DNA obtained from individuals with a self-reported history of depression (n=100) and individuals without a history of depression (n=100) using the Illumina 450K microarray. Our analysis identified 6 significant (Sidak corrected P < 0.05) depression-associated differentially methylated regions (DMRs); the top-ranked DMR was located in exon 1 of the LTB4R2 gene (Sidak corrected P = 1.27 x 10-14). Polygenic risk scores (PRS) for depression were generated and known biological markers of inflammation, telomere length (TL) and IL-6, were measured in DNA and serum samples respectively. Next, we employed a systems-level approach to identify networks of co-methylated loci associated with a history of depression, in addition to depression PRS, TL and IL-6 levels. Our analysis identified one depression-associated co-methylation module (P = 0.04). Interestingly, the depression-associated module was highly enriched for pathways related to immune function and was also associated with TL and IL-6 cytokine levels. In summary, our genome-wide DNA methylation analysis of individuals with and without a self-reported history of depression identified several candidate DMRs of potential relevance to the pathogenesis of depression and its associated immune-dysfunction phenotype.

Genome wide DNA methylation from peripheral white blood cells (PWBCs) from individuals from different cohorts included in the MENA project. Samples included 474 individuals (DiOGenes-UNAV n=52, OBEPALIP n=29, Food4Me-UNAV n=39, GEDYMET n=57, ICTUS n=7, NUGENOB-UNAV n=22, PREDIMED-UNAV n=116, RESMENA n=44, OBEKIT n=96, and NormoP n=12). The Illumina Infinium 450k Human DNA methylation Beadchip or Infinium MethylationEPIC Beadchip (for OBEKIT) was used to obtain DNA methylation profiles across approximately 450,000 CpGs in these samples.

Polybrominated biphenyl (PBB) is an endocrine-disrupting compound which was accidently added to the food supply in Michigan in the 1970’s. Highly exposed individuals and their children have numerous health problems, though the underlying mechanism behind these health problems remains unknown. Other endocrine-disrupting compounds have been linked to epigenetic differences, but no epigenetic studies have been done for PBB. In this study, DNA from the blood of individuals with PBB exposure from the Michigan PBB Registry was interrogated with the MethylationEPIC BeadChip (N = 659). Associations between each of the ~850,000 CpG sites and current, serum PBB levels were tested with a linear regression that controlled for age, sex, and cell type proportions. We show that exposure to PBB is associated with differences in epigenetic marks that suggest that it is acting similarly to estrogen and is associated with dysregulated immune system pathways.

Epigenetic changes may account for the doubled risk to develop schizophrenia in individuals exposed to famine in utero. We therefore investigated DNA methylation in a unique sample of patients and healthy individuals conceived during the great famine in China. Subsequently we examined two case-control samples without famine exposure in whole blood and brain tissue. To shed light on the causality of the relation between famine exposure and DNA methylation we exposed human fibroblasts to nutritional deprivation. In the famine exposed schizophrenia patients we found significant hypermethylation of the dual specificity phosphatase 22 (DUSP22) gene promoter (Chr6:291687-293285) (N=153, p=0.01). In this sample DUSP22 methylation was also significantly higher in patients independent of famine exposure (p=0.025), suggesting that hypermethylation of DUSP22 is also more generally involved in schizophrenia risk. Similarly, DUSP22 methylation was also higher in two separate case-control sample not exposed to famine using DNA from whole blood (N=64, p=0.03) and postmortem brains (N=214, p=0.007). DUSP22 methylation showed strong genetic regulation across chromosomes by a region on chromosome 16 which was consistent with new 3D genome interaction data. The presence of a direct link between famine and DUSP22 transcription was supported by data from cultured human fibroblasts that showed increased methylation (p=0.048) and expression (p=0.019) in response to nutritional deprivation (N=10). These results highlight a first epigenetic locus that is genetically regulated across chromosomes and that is involved in the response to early life exposure to famine and that is relevant for a major psychiatric disorder.

Epigenetic changes may account for the doubled risk to develop schizophrenia in individuals exposed to famine in utero. We therefore investigated DNA methylation in a unique sample of patients and healthy individuals conceived during the great famine in China. Subsequently we examined two case-control samples without famine exposure in whole blood and brain tissue. To shed light on the causality of the relation between famine exposure and DNA methylation we exposed human fibroblasts to nutritional deprivation. In the famine exposed schizophrenia patients we found significant hypermethylation of the dual specificity phosphatase 22 (DUSP22) gene promoter (Chr6:291687-293285) (N=153, p=0.01). In this sample DUSP22 methylation was also significantly higher in patients independent of famine exposure (p=0.025), suggesting that hypermethylation of DUSP22 is also more generally involved in schizophrenia risk. Similarly, DUSP22 methylation was also higher in two separate case-control sample not exposed to famine using DNA from whole blood (N=64, p=0.03) and postmortem brains (N=214, p=0.007). DUSP22 methylation showed strong genetic regulation across chromosomes by a region on chromosome 16 which was consistent with new 3D genome interaction data. The presence of a direct link between famine and DUSP22 transcription was supported by data from cultured human fibroblasts that showed increased methylation (p=0.048) and expression (p=0.019) in response to nutritional deprivation (N=10). These results highlight a first epigenetic locus that is genetically regulated across chromosomes and that is involved in the response to early life exposure to famine and that is relevant for a major psychiatric disorder.

Smoking is common in people who live with HIV infection and has significant adverse effects on HIV outcomes. The impacts of smoking on methylome has been well established in non-HIV populations. However, the smoking’s effects on host methylome in HIV-positive population has not been investigated and it is unknown if smoking-associated DNA methylation link to HIV outcomes. In this study, we applied machine learning methods selected smoking-associated DNA methylation features to predict HIV related frailty and mortality.

Smoking is common in people who live with HIV infection and has significant adverse effects on HIV outcomes. The impacts of smoking on methylome has been well established in non-HIV populations. However, the smoking’s effects on host methylome in HIV-positive population has not been investigated and it is unknown if smoking-associated DNA methylation link to HIV outcomes. In this study, we applied machine learning methods selected smoking-associated DNA methylation features to predict HIV related frailty and mortality.

Peripheral blood from thirty-four monozygotic twin subjects from the general population (n = 17 twin pairs) was collected for epigenomic analysis via Illumina Infinium HumanMethylation450 Beadchip. All subjects were screened for DSM-IV based criteria for both current and lifetime psychiatric disorders. Out of 17 twin pairs, there were: 7 healthy twin pairs where none of the twins of a pair met criteria for any DSM-IV disorder; 6 discordant twin pairs where only one of the twins of each pair met diagnostic criteria; and 4 concordant twin pairs where both twins of a pair met clinical DSM-IV based criteria.

Genetic and environmental risk factors contribute to periodontal disease, but the underlying susceptibility pathways are not fully understood. Epigenetic mechanisms are malleable regulators of gene function that can change in response to genetic and environmental stimuli, thereby providing a potential mechanism mediating risk effects in periodontitis. The aim of this study is to identify epigenetic changes across tissues that are associated with periodontal disease.

Genome wide DNA methylation profiling of cord blood cells obtained from gestational diabetes mellitus (GDM) pregnancies. The Illumina EPIC methylation beadchip array was used to obtain DNA methylation profiles across approximately 850,000 CpG dinucleotide methylation loci in DNA isolated from cord blood. Samples include 165 GDM subjects.

Genome wide DNA methylation profiling of cord blood cells obtained from normal glucose tolerance (NGT) pregnancies. The Illumina EPIC methylation beadchip array was used to obtain DNA methylation profiles across approximately 850,000 CpG dinucleotide methylation loci in DNA isolated from cord blood. Samples include 61 NGT subjects.

Assessing DNA methylation profiles in human blood has become a major focus of epidemiologic inquiry. Understanding variability in CpG-specific DNA methylation over moderate periods of time is a critical first step in identifying CpG sites that are candidates for DNA methylation-based etiologic, diagnostic and prognostic predictors of pathogenesis. Using the Illumina MethylationEPIC [850K] BeadArray, DNA methylation was profiled in paired whole blood samples collected approximately 1 year apart from 35 healthy women enrolled in the Nurses Study II cohort. The median intraclass correlation coefficient (ICC) across all CpG loci was 0.19 [Interquartile Range (IQR) 0.00–0.50]; 74.8% of ICCs were in the low range (0–0.5), 16.9% in the mid-range of ICCs (0.5–0.8), and 8.3% in the high-range of ICCs (0.8–1). ICCs were similar for CpG probes on the 450K Illumina array (median 0.17) and the new probes added to the 850K array (median 0.21). ICCs for CpG loci on the sex chromosomes and known metastable epialleles were high (median 0.71, 0.97, respectively), and ICCs among methylation quantitative trait loci (mQTL) CpGs were significantly higher as compared to non-mQTL CpGs (median 0.73, 0.16, respectively, P < 2 × 10–16). We observed wide variation in DNA methylation stability over a 1-year period. Probes considered non-stable, due to substantial variation over a moderate period of time and with minimal variability across individuals could be removed in large epidemiological studies. Moreover, adjusting for technical variation that arises from using high-dimensional arrays is critical.

Background: The widespread use of accessible peripheral tissues for epigenetic analyses has prompted increasing interest in the study of tissue-specific DNA methylation (DNAm) variation in human populations. To date, characterizations of inter-individual DNAm variability and DNAm concordance across tissues have been largely performed in adult tissues and therefore are limited in their relevance to DNAm profiles from pediatric samples. Given that DNAm patterns in early life undergo rapid changes and have been linked to a wide range of health outcomes and environmental exposures, direct investigations of tissue-specific DNAm variation in pediatric samples may help inform the design and interpretation of DNAm analyses from early life cohorts. In this study, we present a systematic comparison of genome-wide DNAm patterns between matched pediatric buccal epithelial cells (BECs) and peripheral blood mononuclear cells (PBMCs), two of the most widely used peripheral tissues in human epigenetic studies. Specifically, we assessed DNAm variability, cross-tissue DNAm concordance and genetic determinants of DNAm across two independent early life cohorts encompassing different ages. Results: BECs had greater inter-individual DNAm variability compared to PBMCs and highly variable CpGs were more likely to be positively correlated between the matched tissues compared to less variable CpGs. These sites were enriched for CpGs under genetic influence, suggesting that a substantial proportion of DNAm co-variation between tissues can be attributed to genetic variation. Finally, we demonstrated the relevance of our findings to human epigenetic studies by categorizing CpGs from published DNAm association studies of pediatric BECs and peripheral blood. Conclusions: Taken together, our results highlight a number of important considerations and practical implications in the design and interpretation of EWAS analyses performed in pediatric peripheral tissues.

Genome wide DNA methylation profiling of depressed (n=489) and control subjects (n=210) that were recruited at the Max Planck Institute of Psychiatry (MPIP). The Illumina Infinium 450k Human DNA methylation Beadchip was used to obtain DNA methylation profiles based whole blood samples.

Nicolaides-Baraitser syndrome (NCBRS) is a neurodevelopmental disorder caused by pathogenic sequence variants in SMARCA2 which encodes the catalytic component of the chromatin remodeling BAF (SWI/SNF) complex. We identified an NCBRS-SMARCA2 DNA methylation (DNAm) signature of 429 differentially methylated CpG sites in blood cells of individuals with NCBRS (n=8) compared to neurotypical controls (n=23) using the Illumina MethylationEPIC array. The genes to which these CpGs mapped were enriched for roles in cell differentiation, calcium signaling, and neuronal function consistent with NCBRS pathophysiology. The DNAm signature, demonstrating 100% sensitivity and specificity, was used to generated a model enabling classification of variants of unknown significance (VUS) in SMARCA2 as pathogenic (like NCBRS cases) or benign (like controls). Model assignments were concordant with the clinical phenotype and predicted protein effects for most cases; variants within the SMARCA2 ATPase/helicase domain classified as pathogenic and those outside as benign. A patient with a mild NCBRS phenotype and a SMARCA2 VUS distal to the ATPase/helicase domain demonstrated an intermediate DNAm signature profile, suggesting the signature output reflects the phenotype of individual cases. At most of the signature sites, the methylation values for this patient resembled those of either NCBRS cases or controls; the ontology of the genes overlapping these NCBRS- or control-like CpG sites were consistent with the patient?s unique clinical presentation. The NCBRS-SMARCA2 DNAm signature provides alternate means of functional molecular classification of SMARCA2 VUS as benign or pathogenic, as well as providing insight into downstream BAF complex targets.

Genome wide DNA methylation profiling of depressed (n=324) and control subjects (n=209) that were recruited at the Max Planck Institute of Psychiatry (MPIP). The Illumina Infinium 450k Human DNA methylation Beadchip was used to obtain DNA methylation profiles based whole blood samples.

Peripheral blood samples were obtained at baseline and at follow-up visit from 20 participants in the Health, Aging and Body Composition prospective cohort study. Genome-wide CpG methylation was assayed using the Illumina Infinium Human MethylationEPIC (HM850K) microarray. We explored longitudinal changes in CpG methylation from blood leukocytes, and likelihood of a future cancer diagnosis.

We measured 371 genome‐wide DNA methylation profiles of sorted peripheral blood samples from 63 patients with rheumatoid arthritis and 31 unaffected control subjects. Methylation profiles were measured for cell subsets of CD14+ monocytes, CD19+ B cells, CD4+ memory T cells, and CD4+ naive T cells.

We measured the DNA methylation levels at ~800,000 CpG sites from ethnically admixed children in CBMCs at birth and PBMCs age 7 to study the longitudinal dynamics of methylation marks. We found that self-reported race-dependent methylation levels were conserved over time, which helped to suggest that blood methylation levels are robust to environmental exposures during the first 7 years of life.

Childhood and cumulative exposure to trauma increases an individual's lifetime risk for psychiatric and stress-related disorders. This study evaluates DNA methylation in whole blood, with the goal of identifying associaitons between peripheral DNA methylation and psychiatric symptoms.

Multi-locus imprinting Disturbances (MLID) are methylation defects affecting germline-derived Differentially Methylated Regions (gDMRs) and they have been associated with maternal-effect variants causing imprinting disorders in the offspring. In a family with multiple pregnancy losses, a child with Beckwith-Wiedemann syndrome (BWS) and a further child without any features of imprinting disorders, novel compound heterozygous variants in the NLRP5 gene of the mother were found. Locus-specific and whole-genome methylation analysis by using Infinium MethylationEPIC BeadChip (WG-317-1001, Illumina) revealed MLID with different methylation profiles in both the siblings. The proband and the normal sibling were found to cluster with other MLID cases as shown by principal component analysis and unsupervised hierarchical clustering and remain distinct from controls. However, we were unable to cluster MLID cases associated with specific clinical phenotypes. The identification of two novel maternal-effect variants of NLRP5 associated with poly-abortivity and MLID add further evidence to the role of NLRP5 in the maintenance of genomic imprinting in early embryos. Furthermore, our results demonstrate that within these pedigrees MLID can also be present in the progeny with healthy phenotype, indicating that some sort of compensation occurs between altered imprinted loci in these individuals.

Genome wide DNA methylation profiling of monocytes from healthy donors and rheumatoid arthritis patients. The Illumina Infinium MethylationEPIC Beadchip was used to obtain DNA methylation profiles across approximately 850,000 CpGs in CD11b+CD33+CD15neg monocytes isolated from PBMCs of 17 healthy donors and 47 rheumatoid arthritis patients with different disease activity scores (DAS28).

Acquired resistance of chronic lymphocytic leukemia (CLL) to chemotherapy is an important clinical problem and is often caused by cytogenetic aberrations or gene mutations affecting the ATM-p53 DNA damage response pathway or other pathways. However, there are also a lot of resistant cases without detectable mutations and we decided to check whether there are specific epigenetic changes at the level of DNA methylation that might underlie resistance development in CLL. We used Illumina Infinium HumanMethylation450 BeadChips to obtain DNA methylation profiles of 71 CLL patients with different responses to chemotherapy. Fifty-one patients were subjects of the CLL2O clinical trial and 36 of them were categorized as relapsed/refractory after treatment with fludarabine- or bendamustine-containing regimens, whereas the other 15 patients as well as 20 additional patients not on the trial were untreated at the time of sampling. Although we could not correlate chemoresistance with epigenetic changes, we believe that the dataset is valuable and can be used by researchers to test other hypotheses, especially as the patients are well characterized regarding different prognostic and molecular markers (IGHV mutation status, chromosome aberrations, TP53 mutation status, etc.).

Genome wide DNA methylation profiling of monocytes from healthy donors, systemic inflammatory response syndrome (SIRS) and septic patients. The Illumina Infinium MethylationEPIC Beadchip was used to obtain DNA methylation profiles across approximately 850,000 CpGs in CD14+CD66bneg monocytes isolated from PBMCs of 11 healthy donors, 4 SIRS and 14 septic patients.

Genome wide DNA methylation profiling of human blood samples. The Illumina Infinium EPIC DNA methylation Beadchip was used to obtain DNA methylation profiles Survival has increased in early stage breast cancer (BC), and the late effects of cancer treatment can persist for decades. The molecular mechanisms underlying acceleration of age-related diseases after chemotherapy and radiotherapy are poorly understood. We examined epigenetic changes in peripheral blood in early stage BC patients undergoing either adjuvant radiotherapy, or adjuvant chemotherapy and radiotherapy. DNA methylation experiments were performed on peripheral blood samples from women collected prior to and following completion of adjuvant therapy. Methylation profiles were used to estimate three measures of epigenetic age acceleration - intrinsic, extrinsic, and phenotypic - as well as estimated cell counts.

Genome wide DNA Methylation in PBMC of untreated HIV-chronic individuals with different HIV control. For a total of 70 PBMC samples we determined DNA Methylation levels of more than 450,000 CpG sites with the platform Infinium HumanMethylation450 BeadChip (450K, Illumina). Finally, we compared DNA methylation between HIV-High (>50,000 HIV RNA copies/ml, n=29) and HIV-Low (<10,000 HIV RNA copies/ml, n=41) individuals and identified 2,649 gene-annotated CpG positions that were differentially methylated between the two groups.

Age-related CpG (AR-CpG) sites are currently the most promising molecular markers for age estimation. However, AR-CpG sites for the Han Chinese population have not yet been systematically identified. Besides, there may be high-performance AR-CpG sites beyond the coverage of the commonly used Illumina HumanMethylation450 BeadChip that covers over 450,000 CpG sites (450K), which accounts only 1.6% of CpG sites in the human genome. Therefore, we initiated a project to perform genome-wide methylation analysis on whole blood samples from 42 healthy Han Chinese individuals (21 males and 21 females, 18–62 years) using the newly developed Illumina Infinium MethylationEPIC array that assesses over 850,000 CpG sites (850K) to identify AR-CpG sites for forensic use systematically. The 850K methylation array contains > 90% of 450K CpG sites but adds 413,745 CpG sites. As expected, we not only replicated several high-performance AR-CpG sites previously discovered using the Illumina 450K BeadChip, such as cg16867656 (ELOVL2), cg22454769 (FHL2), and cg10501210 (C1orf132), but also identified 41 (60.3%), 34 (22.5%), and 382 (48.7%) novel AR-CpG sites from the methylation profiles of 21 males, 21 females, and all individuals, respectively.

DNA methylation may be involved in development of type 1 diabetes (T1D), but previous epigenome-wide association studies were conducted among cases with clinically diagnosed diabetes. Using multiple pre-disease peripheral blood samples on the Illumina 450K and EPIC platforms, we investigated longitudinal methylation differences between 87 T1D cases and 87 controls from the prospective Diabetes Autoimmunity Study in the Young (DAISY) cohort. Change in methylation with age differed between cases and controls in 10 regions. Average longitudinal methylation differed between cases and controls at two genomic positions and 28 regions. Some methylation differences were detectable and consistent as early as birth, including before and after the onset of preclinical islet autoimmunity. Results map to transcription factors, other protein coding genes, and non-coding regions of the genome with regulatory potential. The identification of methylation differences that predate islet autoimmunity and clinical diagnosis may suggest a role for epigenetics in T1D pathogenesis.

Using a longitudinal study design, we quantified DNA methylation across the genome in a cohort of 30 elderly patients (average age = 77.9 years (range 62-91)) undergoing major surgery (either elective colorectal surgery, elective hip replacement surgery, and emergency hip surgery following fracture). From each individual, detailed clinical blood measures were collected and DNA methylation was profiled using the Illumina Human Methylation 450 array (g450K arrayh) (Illumina Inc. San Diego, California) in DNA samples isolated from purified PBMCs collected at three time-points: i) immediately before surgery (baseline (BL)), ii) in the morning of post-operative day 1 (POD1) and iii) between post-operative day 4 and 7 (POD4/7) prior to discharge from hospital.

Clonal and subclonal evolution is involved in the progression of chronic lymphocytic leukemia (CLL). Evolution can work to select not only genetic mutations, but also epigenetic states. Here we performed a long-term longitudinal DNA methylation profiling study of CLL patients to look for associations of epigenetic evolution to different disease courses. In line with the genetic data, large-scale methylation evolution was not present in any of the evaluated long-term untreated (n = 3) and relapsed (n = 2) patients displaying clonal changes of linear type while 3 of the 5 examined refractory patients featured profound changes in DNA methylation.

Genome-wide DNA methylation profiling of over 850,000 methylation sites carried out using the Illumina MethylationEPIC BeadChip was used to compare 18 babies born with congenital Zika virus microcephaly, 7 babies exposed to Zika virus in utero but born without clinical signs, and 20 control unexposed unaffected babies

Genome wide DNA methylation assays was conducted using the Illumina Infinium MethylationEPIC BeadArray technology (Methyl850K chip) that allows genome-wide DNA methylation analysis of 866,836 CpG sites. Samples included 11 psychiatric cases and 12 healthy controls balanced by age decade and sex.

DNA Methylation was analyzed in tuberculosis patients without HIV at baseline and 6 months after completion of successful therapy. DNA methylation was also evaluated in TB patients with HIV and in healthy controls without Tuberculosis. 500ng of gDNA was bisulfite treated prior to running the Illumina Infinium MethylEPIC array

Genome-wide patterns of DNA methylation were quantified using the Illumina Infinium HumanMethylation450 BeadChip (“450K array”) in DNA samples isolated from blood for schizophrenia cases and controls. This samples were profiled as part of a wider study where they were meta-analysed with other cohorts.

Markers of biological ageing have potential utility in primary care and public health. We developed a model of age based on untargeted metabolic profiling across multiple platforms, including nuclear magnetic resonance spectroscopy and liquid chromatography-mass spectrometry in urine and serum, within a large sample (N=2,239) from the UK Airwave cohort. We validated a subset of model predictors in a Finnish cohort including repeat measurements from 2,144 individuals. DNA methylation age was assessed for 1,110 participants using the Infinium HumanMethylation EPIC BeadChip. We investigated the determinants of accelerated ageing, including lifestyle and psychological risk factors for premature mortality. The metabolomic age model was well correlated with chronological age (mean r=0.86 across independent test sets). Increased metabolomic age acceleration (mAA) was associated after false discovery rate (FDR) correction with overweight/obesity, diabetes, heavy alcohol use and depression. DNA methylation age acceleration measures were uncorrelated with mAA. Increased DNA methylation phenotypic age acceleration (N = 1,110) was associated after FDR correction with heavy alcohol use, hypertension and low income. In conclusion, metabolomics is a promising approach for the assessment of biological age and appears complementary to established epigenetic clocks.

Epidemiological studies in humans suggest that acquired paternal traits, such as obesity, are associated with a higher risk of fathering small for gestational age offspring. Studies in non-human mammals suggest that such associations could be mediated by DNA methylation changes in spermatozoa that influence offspring development in utero. Human obesity is associated with differential DNA methylation in peripheral blood. It is unclear, however, whether this differential DNA methylation is reflected in less readily available tissues such as spermatozoa. In this study, we profiled genome-wide DNA methylation with the Infinium MethylationEPIC array in matched samples of human blood and sperm from lean (discovery n = 47; replication n = 21) and obese (n = 22) healthy males of proven fertility. To characterize sperm-specific DNA methylation signatures, we compared spermatozoal DNA methylation data to that of nearly 6,000 somatic tissue samples available on the Gene Expression Omnibus database. We studied covariation patterns between whole blood and sperm and investigated consistent obesity-associated DNA methylation differences.

Genome wide DNA methylation profiling of peripheral blood samples of moderate-to-severe psoriasis patients treated with anti-TNF drugs. Patients were distributed on Excellent Responders (ER) if they achieved PASI90 (a 90% reduction with respect to baseline PASI) at 3 and 6 months of treatment with anti-TNF drugs and Partial responders if they did not achieve a PASI75 (a 75% reduction with respect to baseline PASI) at 3 and 6 months of treatment. The Illumina Infinium 450k Human DNA methylation Beadchip v1.2 was used to obtain DNA methylation profiles across approximately 485,000 CpGs in 49 ER and 21 PR which were obtained from peripheral blood samples of anti-TNF drug treated patients. We have searched for pharmaoepigenetic biomarkers of anti-TNF response in moderate-to-severe psoriasis patients.

Genome-wide patterns of DNA methylation were quantified using the Illumina Infinium HumanMethylationEPIC BeadChip (“EPIC array”) in DNA samples isolated from blood for schizophrenia cases, first episode psychosis patients and controls. These samples were profiled as part of a wider study where they were meta-analysed with other cohorts.

Genome-wide patterns of DNA methylation were quantified using the Illumina Infinium HumanMethylation450K BeadChip (“450K array”) in DNA samples isolated from blood for schizophrenia cases, first episode psychosis patients and controls. These samples were profiled as part of a wider study where they were meta-analysed with other cohorts.

Genome-wide patterns of DNA methylation were quantified using the Illumina Infinium EPIC array (“EPIC array”) in DNA samples isolated from buccal swabs collected at ages 5, 10 and 18 and whole blood samples collected at age 18 from 118 Monozygotic twin pairs from the Environmental Risk (E-Risk) Longitudinal Twin Study. Comparison of DNA methylation profiles of 233 age 18 blood samples with data on EPIC and Illumina 450K methylation arrays.

The Val122Ile mutation in Transthyretin (TTR) gene causes a rare, difficult to diagnose hereditary form of cardiac amyloidosis. This mutation is most common in the United States and mainly present in people of African descent. The carriers have an increased risk of congestive heart failure, peripheral edema, and several other non-cardiac phenotypes such as carpal tunnel syndrome, and arthroplasty which are top reasons for ambulatory/outpatient surgeries in the country. We conducted first-ever epigenome-wide association study in Val122Ile carriers of African descent for heart disease (HD) and multiple outpatient surgeries (OS) - an early disease indicator. DNA was extracted from whole blood of Yale-Penn participants using the EZ-96 DNA methylation kit (Zymo Research, CA, USA). DNA methylation was assayed using the Illumina Infinium MethylationEPIC chip quantifying >850,000 CpG sites and imaged on the Illumina iScan system at YCGA. The methylation intensity data (*.idat files) was exported for analysis using the manufacturer's recommended protocol using the GenomeStudio methylation module.

Epigenetic profiles in peripheral blood samples from 59 subjects (in two separate U.S. Military training sessions) were screened using Illumina Infinium MethylationEPIC BeadChips, session 2 (31 subjects) were also screened post-exposure to a controlled, low-level blast during a 3-day explosive breaching course. Participants had varying numbers of exposures to blast over their military careers (empirically defined as high ≥ 40, and conversely, low < 39 breaching exposures) at baseline. Daily self-reported physiological symptoms were recorded.

Prion diseases are fatal and transmissible neurodegenerative disorders caused by the misfolding and aggregation of prion protein. Although recent studies have implicated epigenetic variation in common neurodegenerative disorders, no study has yet explored their role in human prion diseases. Here we profiled genome-wide blood DNA methylation in the most common human prion disease, sporadic Creutzfeldt-Jakob disease (sCJD). Our case-control study (n=219), when accounting for differences in cell type composition between individuals, identified 38 probes at genome-wide significance (p < 1.24x10-7). Nine of these sites were taken forward in a replication study, performed in an independent case-control (n=186) cohort using pyrosequencing. Sites in or close to FKBP5, AIM2 (2 probes), UHRF1, KCNAB2, PRNP, ANK1 successfully replicated. The blood-based DNA methylation signal was tissue- and disease-specific, in that the replicated probe signals were unchanged in case-control studies using sCJD frontal-cortex (n=84), blood samples from patients with Alzheimer’s disease, and from inherited and acquired prion diseases. Machine learning algorithms using blood DNA methylation array profiles accurately distinguished sCJD patients and controls. Finally, we identified sites whose methylation levels associated with prolonged survival in sCJD patients. Altogether, this study has identified a peripheral DNA methylation signature of sCJD with a variety of potential biomarker applications.

Genome wide DNA methylation profiling of normal and recent onset psychosis samples . The Infinium Human Methylation 850 K BeadChips was used to obtain DNA methylation profiles across approximately 853 307 CpGs in samples. Samples included 50 normal , 84 recent onset psychosis.

We performed a whole-genome DNA methylation analysis (Infinium HumanMethylation450 BeadChip) on peripheral whole blood of 23 twin pairs (10 monozygotic and 13 dizygotic) heterogeneously (4 concordant and 19 discordant) affected by Congenital Hypothyroidism (CH) at birth.

Social anxiety disorder (SAD) is a psychiatric disorder characterized by extensive fear in social situations. Multiple genetic and environmental factors are known to contribute to its pathogenesis. One of the main environmental risk factors is early life adversity (ELA). Evidence is emerging that epigenetic mechanisms such as DNA methylation might play an important role in the biological mechanisms underlying SAD and ELA. To investigate the relationship between ELA, DNA methylation, and SAD, we performed an epigenome-wide association study for SAD and ELA examining DNA from whole blood of a cohort of 143 individuals using DNA methylation arrays. We identified two differentially methylated regions (DMRs) associated with SAD located within the genes SLC43A2 and TNXB. As this was the first epigenome-wide association study for SAD, it is worth noting that both genes have previously been associated with panic disorder. Further, we identified two DMRs associated with ELA within the SLC17A3 promoter region and the SIAH3 gene and several DMRs that were associated with the interaction of SAD and ELA. Of these, the regions within C2CD2L and MRPL28 showed the largest difference in DNA methylation. Lastly, we found that two DMRs were associated with both the severity of social anxiety and ELA, however, neither of them was found to mediate the contribution of ELA to SAD later in life. Future studies are needed to replicate our findings in independent cohorts and to investigate the biological pathways underlying these effects.

The aim of this study was to identify ASD vulnerability components, explore possible vulnerability subgroups, and evaluate environmental contribution to phenotypic variability. We performed PCA and cluster analysis using ASD risk factor data. We found that PC1 had a higher correlation with psychosocial stress (maternal stress, maternal education, and social class), and PC2 a higher correlation with biological factors (Psychiatric Family History and Gestational Complications). Clustering analysis of PCA scores using bootstrap approach showed two clusters. Comparing the methylome between clusters we found 11.879 DMPs (p<0.05), and their CpG sites were enriched in VMRs, most showing environmental and genetic influences. Hypermethylated probes presented higher rates in different regulatory regions associated with functional SNPs, indicating that the subgroups may have different affected regulatory regions and their liability to disease explained by common variations. Vulnerability score moderated by epigenetic clock was associated with Vineland Total score (p=0.0036, adjR2=0.31), suggesting risk factors with stress burden can influence phenotype.

Infinium Methylation 450 K was used to profile the epigenetic differences in 24 children between two timepoints: 12 months (baseline group) and 24 months and to elucidate the methylation differences between 12 high and 12 low PCV-13 booster vaccine responders, in order to identify pathways that show significant changes over time and those that are associated with a more robust immune response.

Genome wide DNA methylation profiling of 65 congenital imprinting disorder samples, 45 BWS and 22 SRS. The Illumina Infinium HumanMethylation450 BeadChips was used to obtain DNA methylation profiles across approximately 485,000 CpGs in blood samples.

Obesity has been linked to lifestyle and recently have been associated to DNA methylation changes that may cause alterations in the adipogenesis and lipid storage processes and contribute to the pathological state. We enrolled Obese (Ob) and Normal Weight (NW) women. We observed that DNA methylation patterns are different between normal weight and obese women. This can alter gene expression patterns affecting adipogenesis and lipid storage. This results confirms that an obesogenic lifestyle can promote epigenetic changes in the human DNA.

Genome-wide DNA methylation profiling of peripheral blood from 164 SARS-CoV-2 positive, 296 SARS-CoV-2 negative, and 65 other respiratory infection patient samples. Samples were profiled on a custom Illumina Infinium HumanMethylation BeadChip array including all MethylationEPIC-B4 probes and additional custom content targeting immune genes. SARS-CoV-2 positivity is defined by a positive RT-PCR test. "Other infection" samples are SARS-CoV-2 negative and were tested with a panel of common human acute respiratory infection pathogens.

Patients infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), responsible for the coronavirus disease 2019 (COVID-19), exhibit a wide spectrum of disease behavior. Since DNA methylation has been implicated in the regulation of viral infections and the immune system, we performed an epigenome- wide association study (EWAS) to identify candidate loci regulated by this epigenetic mark that could be involved in the onset of COVID-19 in patients without comorbidities.

Background: It is well-established that cancer treatment substantially increases risk of long-term adverse health outcomes among childhood cancer survivors. However, there is limited research on the underlying mechanisms. To elucidate the pathophysiology and a possible causal pathway from treatment exposures to cardiometabolic conditions, we conducted epigenome-wide association studies (EWAS) to identify DNA methylation (DNAm) sites associated with cancer treatment exposures and examined whether treatment-associated DNAm sites mediate associations between specific treatments and cardiometabolic conditions. Methods: We included 2,052 survivors (median age 33.7 years) of European ancestry from the St. Jude Lifetime Cohort Study, a retrospective hospital-based study with prospective clinical follow-up. Cumulative doses of chemotherapy and region-specific radiation were abstracted from medical records. Seven cardiometabolic conditions were clinically assessed. DNAm profile was measured using MethylationEPIC BeadChip with blood-derived DNA. Results: By performing multiple treatment-specific EWAS, we identified 935 5’-cytosine-phosphate-guanine-3′ (CpG) sites mapped to 538 genes/regions associated with one or more cancer treatments at epigenome-wide significance level (P<9×10-8). Among the treatment-associated CpGs, 8 were associated with obesity, 63 with hypercholesterolemia, and 17 with hypertriglyceridemia (False-Discovery-Rate-Adjusted P<0.05). We observed substantial mediation by methylation at four independent CpGs (cg06963130, cg21922478, cg22976567, cg07403981) for association between abdominal field radiotherapy (abdominal-RT) and risk of hypercholesterolemia (70.3%) and by methylation at three CpGs (cg19634849, cg13552692, cg09853238) for association between abdominal-RT and hypertriglyceridemia (54.6%). In addition, three CpGs (cg26572901, cg12715065, cg21163477) partially mediated the association between brain-RT and obesity with 32.9% mediation effect and two CpGs mediated the association between corticosteroids and obesity (cg22351187, 14.2%) and between brain-RT and hypertriglyceridemia (cg13360224, 10.5%). Notably, several mediator CpGs reside in the proximity of well-established dyslipidemia genes: cg21922478 (ITGA1) and cg22976567 (LMNA). Conclusions: In childhood cancer survivors, cancer treatment exposures are associated with DNAm patterns present decades following the exposure. Treatment-associated DNAm sites may mediate the causal pathway from specific treatment exposures to certain cardiometabolic conditions, suggesting the utility of DNAm sites as risk predictors and potential mechanistic targets for future intervention studies.

Genome wide DNA methylation profiling of peripheral blood cells from WHS and several disease patients. The Illumina Infinium EPIC Human DNA methylation Beadchip was used to obtain DNA methylation profiles across approximately 850,000 CpGs in peripheral blood samples. Samples included, 20 WHS, 1 patient with heterozygous deletion in 4p16.2p15.31, 2 Sotos syndrome patients, 2 Kabuki syndrome patients, 1 CHARGE syndrome patient, and 3 patients who harbor NSD2 de novo variants.

Genome-wide DNA methylation analysis of COVID-19 severity using the Illumina HumanMethylationEPIC microarray platform to analyze over 850,000 methylation sites, comparing COVID-19 patients with patients presenting with respiratory symptoms, but negative for COVID-19, using whole blood tissue.

Undifferentiated arthritis (UA) is the term used to cover all the cases of arthritis that do not fit a specific diagnosis. A high proportion of UA patients can progress to rheumatoid arthritis (RA) or a different definite rheumatic disease, while others undergo spontaneous remission. In this study, we performed DNA methylation profiling of a UA cohort, in which progression into RA occurs for a significant proportion of the patients.

Scleroderma refers to a group of chronic fibrotic immune-mediated diseases of unknown etiology. Characterizing epigenetic changes in childhood-onset scleroderma, systemic sclerosis or localized scleroderma, has not been previously performed. The aim of this study was to assess DNA methylation differences and similarities between juvenile systemic sclerosis (jSSc) and juvenile localized scleroderma (jLS) compared to matched healthy controls. Genome-wide DNA methylation changes in peripheral blood mononuclear cell samples were assessed using the MethylationEPIC array followed by bioinformatic analysis and limited functional assessment. We identified a total of 105 and 144 differentially methylated sites compared to healthy controls in jSSc and jLS, respectively. The majority of differentially methylated sites and genes represented were unique to either jSSc or jLS suggesting a different underlying epigenetic pattern in both diseases. Among shared differentially methylated genes, methylation levels in a CpG site in FGFR2 can distinguish between LS and healthy PBMCs with a high accuracy. Canonical pathway analysis revealed that inflammatory pathways were enriched in genes differentially methylated in jSSc, including STAT3, NF-κB, and IL-15 pathways. In contrast, the HIPPO signaling pathway was enriched in jLS. Our data also suggest a potential role for NOTCH3 in both jSSc and jLS, and revealed a number of transcription factors unique to each of the two diseases. In summary, our data revealed important insights into jSSc and jLS and suggest a potentially novel epigenetic diagnostic biomarker for LS.

Rheumatoid arthritis (RA) is a chronic inflammatory disease of the joints that has been associated with changes in the blood methylome. There is high interest to determine if this accessible epigenetic variation is associated with relevant clinical outcomes.

This study aimed to determine whether methylation signature of peripheral blood mononuclear cells (PBMCs) prior to the start of the first cycle of DOX-based chemotherapy could predict the risk of cardiotoxicity in breast cancer patients as well as determine if DOX treatment changed methlation profiles. The Illumina Infinium 450 Human DNA methylation Beadchip was used to obtain DNA methylation profiles across approximately 450k CpGs PBMCs samples before and after treatment. Samples included 10 samples from patients with normal ejection fraction after DOX treatment, 9 samples from patients with abnormal ejection fraction (indicative of cardiotoxicity) after DOX treatment.

Konzo, a disease characterized by sudden, irreversible spastic paraparesis, affecting up to 10% of the population in some regions of Sub-Saharan Africa during outbreaks and is strongly associated with dietary exposure to cyanogenic bitter cassava. The molecular mechanisms underlying the development of konzo, remain largely unknown. Here, through an analysis of 16 individuals with konzo and matched healthy controls from the same outbreak zones, we identified 117 differentially methylated loci involved in numerous biological processes that may identify cyanogenic- sensitive regions of the genome, providing the first study of epigenomic alterations associated with sub-lethal cyanide exposure and a clinical phenotype.

DNA methylation microarrays have been extensively used for understanding cell type composition in complex tissue samples. Here we expand on existing libraries for reference-based deconvolution of blood DNA methylation data assayed using the Illumina HumanMethylationEPIC array to include 12 different leukocyte subtypes (neutrophils, eosinophils, basophils, monocytes, B cells naïve and memory, CD4+ and CD8+ naïve and memory cells, natural killers, and T regulatory cells). Application of the IDOL algorithm for identifying optimal libraries for the deconvolution of blood-derived DNA methylation data led to a library consisting of 1200 CpGs. The accuracy of deconvolution estimates obtained using our IDOL-optimized library was evaluated using artificial mixtures with known cellular composition and in samples were both whole-blood DNA methylation data and FACS information were available. We further showcase potential applications of our expanded library using publicly available cancer, aging, and autoimmune disease data sets.

Prognosis for cardiogenic shock patients under ECMO was our study goal. Success defined as survived more than 7 days after ECMO installation and failure died or had multiple organ failure in 7 days. Total 34 cases were enrolled, 17 success and 17 failure. Peripheral blood mononuclear cells collected at ECMO installation 0, 2 hours and removal were analyzed.

Traditional Chinese medicine emphasizes treatment based on syndrome differentiation. This study aimed to clarify the characteristics of DNA methylation expression profiles in peripheral blood mononuclear cells in patients with psoriasis and analyze the differences in these profiles among different traditional Chinese medicine syndromes of psoriasis in order to provide a material basis for the diversity of these syndromes. Blood samples were collected from 32 participants, including 13 patients with psoriatic blood heat syndrome, 13 patients with psoriatic blood stasis syndrome, and 6 healthy controls. Peripheral blood mononuclear cells were extracted and subjected to DNA quality inspection. An Illumina Human Methylation 850k chip was used to sequence each group of samples. After screening out differentially methylated sites, the distribution of the corresponding differentially methylated genes on the chromatin was determined. According to gene annotation classification and CpG island annotation classification, the differentially methylated regions between sample groups were screened, and Gene Ontology and KEGG pathway analyses were used to perform functional analysis of differentially methylated genes. Finally, the differentially methylated genes closely correlating with psoriasis severity were screened using Spearman’s correlation analysis.

Non-muscle-invasive bladder cancer (NMIBC) patients receive frequent monitoring because ≥ 70% will have recurrent disease. However, screening is invasive, expensive, and associated with significant morbidity making bladder cancer the most expensive cancer to treat per capita. There is an urgent need to expand the understanding of markers related to recurrence and survival outcomes of NMIBC. Our results expand on the knowledge of immune profiles and methylation alteration associated with NMIBC outcomes and represent a first step toward the development of DNA methylation-based biomarkers of tumor recurrence.

The identification of predictive markers in an early undifferentiated arthritis (UA) patients is pivotal for selecting appropriate therapies to avoid a poor prognosis. In this work, we investigated the association between clinical features and DNA methylation patterns in monocytes from UA patients to seek potential prognostic biomarkers.

Genome wide DNA methylation assays was conducted using the Illumina Infinium MethylationEPIC BeadArray technology (Methyl850K chip) that allows genome-wide DNA methylation analysis of 866,836 CpG sites. We included baseline and 2-year follow-up samples from 25 persons with mild cognitive impairment (cases) and 20 persons with cognitively normal (controls). Sample was balanced by age and sex.

Introduction: Nutriepigenetic markers are predictive responses associated with changes in human "surrounding" environmental conditions, which may influence metabolic diseases. Although rich in calories, Western diets could be linked with the deficiency of micronutrients, resulting in the downstream of epigenetic and metabolic effects and consequently in obesity. Zinc (Zn) is an essential nutrient associated with distinct biological roles in human health. Despite its importance in metabolic processes, little is known about the Zn-epigenetic. Thus, the present study aimed to identify the epigenetic variables associated with Zn daily ingestion (ZnDI) and serum Zinc (ZnS) levels in women with and without obesity. Materials and methods: this is a case-control, non-randomized, single-center study conducted with 21 women allocated into two groups: Control Group (CG), composed of 11 women without obesity, and Study Group (SG), composed of 10 women with obesity. Anthropometric measurements, ZnDI, and ZnS levels were evaluated. Also, the leukocyte DNA was extracted for DNA methylation analysis using the 450k Illumina BeadChips. The Epigenetic Clock was calculated by the Horvath method. The ChAMP package selected the Differentially Methylated Regions (DMRs). Results: The SG had lower ZnS levels than the CG. Moreover, in SG, the ZnS levels were negatively associated with the epigenetic age acceleration. The DMR analysis revealed 37 DMRs associated with ZnDI and ZnS levels. The DMR of the PM20D1 gene was commonly associated with ZnDI and ZnS levels and was hypomethylated in the SG. Conclusion: Our findings provide new information on Zn's modulation of DNA methylation patterns and bring new perspectives for understanding the nutriepigenetic mechanisms in obesity.

Background: Most children and adolescents infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) develop a mild coronavirus disease 2019 (COVID-19) that usually does not require medical intervention. However, a small proportion of pediatric patients develop a severe clinical condition, Multisystem Inflammatory Syndrome in Children (MIS-C). The involvement of epigenetics in the control of the immune response and viral activity prompted us to carry out an epigenomic study to uncover target loci regulated by DNA methylation that could be altered upon the appearance of MIS-C. Methods: Peripheral blood samples were recruited from 43 confirmed MIS-C patients with a median age of 7.7 years, most of whom were of West-Eurasian origin. Four or more organ systems were involved in the majority of patients. 69 non-COVID-19 pediatric samples and 15 COVID-19 pediatric samples without MIS-C were used as controls. The cases in the two groups were mixed and divided into discovery (MIS-C = 29 and non-MIS-C = 56) and validation (MIS-C = 14 and non-MIS-C = 28) cohorts, and balanced for age, gender and ethnic background. We interrogated 850,000 CpG sites of the human genome for DNA methylation variants. Findings: The DNA methylation content of 33 CpG loci was linked with the presence of MIS-C. Of these sites, 18 (54.5%) were located in described genes. The top candidate gene was the immune T-cell mediator ZEB2; and others highly ranked candidates included the regulator of natural killer cell functional competence SH2D1B; VWA8, which contains a domain of the Von Willebrand factor A involved in the pediatric hemostasis disease; and human leukocyte antigen complex member HLA-DRB1; in addition to pro-inflammatory genes such as CUL2 and AIM2. The identified loci were used to construct a DNA methylation profile (EPIMISC) that was associated with MIS-C in both cohorts. The EPIMISC signature was also overrepresented in Kawasaki disease patients, a childhood pathology with also a possible viral trigger, that shares many of the clinical features of MIS-C. Interpretation: We have characterized DNA methylation loci that are associated with the onset of MIS-C. The identified genes are likely contributors to the characteristic exaggerated host inflammatory response observed in these patients. The described epigenetic signature could also provide new targets for more specific therapies for the disorder.

Genome-wide DNA Methylation Data from Illumina HumanMethylationEPIC arrays for whole blood samples from 570 healthy individuals. Raw IDAT files are available for a subset of 403 samples on EGA. Raw data (IDAT files) and associated phenotype information are available for all individuals included in this study (n=570) directly from CIBMTR. Data are available under controlled access release upon reasonable request and execution of a data use agreement. Requests should be submitted to CIBMTR at info-request@mcw.edu and include the study reference IB17-04.

Inflammaging is the name given to this chronic and asymptomatic inflammatory state generated by the aging process and by chronic and infectious diseases. Chronic diseases can alter the epigenetic profile of tissues leading to an increased epigenetic aging and some of the differentially methylated genes can be used to characterize the disease and as disease biomarkers. Leprosy is an infection caused by Mycobacterium leprae and can be lifelong, exposing the individual to a low-grade inflammation environment. In this study, we evaluated the inflammatory profile in 35 individuals from a leprosy endemic area from Brazil by cytokine analysis with a luminex assay. In adition, we investigated the leucocytes genome-wide DNA methylation profile using the Infinium MethylationEPIC BeadChip array. A total number of 31 CpGs were significantly methylated, between cases and controls, which belonged to 8 genes potentially peripherally perturbed in the pathogenesis of the disease. Affected individuals from endemic area were epigenetically aged in relation to control samples and interesting control samples from endemic area were aged in relation to unaffected control samples from non-endemic area. In conclusion, leprosy showed a deregulated methylation profile in comparison with control samples. The epigenetic analysis provided valuable clues for further investigations in understanding peripherical blood leprosy alterations and the use of these genes as biomarkers.

EPIC array data were generated from 2 MDD case control cohorts. EWAS was performed in each cohort, followed by meta-analysis between the 2 cohort. Cohort 1: A total of 191 blood samples from 112 patients with MDD was collected up till the interim analysis (wave 1 samples) from an observational clinical study OBSERVEMDD0001 (ClinicalTrials.gov Identifier: NCT02489305) compared to 32 healthy controls; Cohort 2: The MDD cases (N = 359) were drawn from the Molecular Biomarkers of Antidepressant Response study compared to 68 healthy controls.

We performed a whole-genome DNA methylation analysis using EPIC Illumina BeadArrays on a cohort of 187 “Italian” COVID-19 patients (123 mild and 64 severe) to identify epigenetic markers underlying the worst evolution of the disease (death or Intensive Care Unit admission for mechanical ventilation support).

Background: Pre-diabetes condition precedes the Diabetes Mellitus (DM) disease and is a critical period for hyperglycemia treatment, especially for menopausal women, considering all metabolic alterations due to hormonal changes. Recently, the literature has demonstrated the role of physical exercise in epigenetic reprogramming to modulate the gene expression patterns of metabolic conditions, such as hyperglycemia, preventing DM development. In the present study, we hypothesized that physical exercise training could modify the epigenetic patterns of women with poor glycemic control. Methods: 48 post-menopause women aged 60.3±4.5 years were divided according to the fasting blood glucose levels into two groups: Prediabetes Group, PG (n=24) and Normal Glucose Group, NGG (n=24). All participants performed 14 weeks of physical exercise three times a week. The Infinium Methylation EPIC BeadChip measured the participants’ Different Methylated Regions (DMRs). Results: Before the intervention, the PG group had 12 DMRs compared to NGG. After the intervention, five DMRs remained different. Interestingly, when comparing the PG group before and after training, 118 DMRs were found. The enrichment analysis revealed that the genes were related to different biological functions such as energy metabolism, cell differentiation, and tumor suppression. Conclusion: Physical exercise is a relevant alternative in treating hyperglycemia and preventing DM in post-menopause women with poor glycemic control.

Background: Panic disorder (PD) is characterized by recurrent panic attacks and higher affection of women as compare to men. The lifetime prevalence of PD is about 2-3 % in the general population leading to tremendous distress and disability. Etiologically, genetic and environmental factors, such as stress, contribute to the onset and relapse of PD. In the present study, we investigated epigenome-wide DNA methylation (DNAm) in respond to a cumulative, stress-weighted life events score (wLE) in patients with PD and its boundary to major depressive disorder (MDD), frequently co-occurring with symptoms of PD. Methods: DNAm was assessed by the Illumina HumanMethylation450 BeadChip. In a meta-analytic approach, epigenome-wide DNAm changes in association with wLE were first analyzed in two PD cohorts (with a total sample size of 183 PD patients and 85 healthy controls) and lastly in 102 patients with MDD to identify possible overlapping and opposing effects of wLE on DNAm. Additionally, analysis of differentially methylated regions (DMRs) was conducted to identify regional clusters of association. Results: Two CpG-sites presented with p-values below 1x10-05 in PD: cg09738429 (p=6.40x10-06, located in an intergenic shore region in next proximity of PYROXD1) and cg03341655 (p=8.14x10-06, located in the exonic region of GFOD2). The association of DNAm at cg03341655 and wLE could be replicated in the independent MDD case sample indicating a diagnosis independent effect. Genes mapping to the top hits were significantly upregulated in brain and top hits have been implicated in the metabolic system. Additionally, two significant DMRs were identified for PD only on chromosome 10 and 18, including CpG-sites which have been reported to be associated with anxiety and other psychiatric phenotypes. Conclusion: This first DNAm analysis in PD reveals first evidence of small but significant DNAm changes in PD in association with cumulative stress-weighted life events. Most of the top associated CpG-sites are located in genes implicated in metabolic processes supporting the hypothesis that environmental stress contributes to health damaging changes by affecting a broad spectrum of systems in the body.

Background: Panic disorder (PD) is characterized by recurrent panic attacks and higher affection of women as compare to men. The lifetime prevalence of PD is about 2-3 % in the general population leading to tremendous distress and disability. Etiologically, genetic and environmental factors, such as stress, contribute to the onset and relapse of PD. In the present study, we investigated epigenome-wide DNA methylation (DNAm) in respond to a cumulative, stress-weighted life events score (wLE) in patients with PD and its boundary to major depressive disorder (MDD), frequently co-occurring with symptoms of PD. Methods: DNAm was assessed by the Illumina HumanMethylation450 BeadChip. In a meta-analytic approach, epigenome-wide DNAm changes in association with wLE were first analyzed in two PD cohorts (with a total sample size of 183 PD patients and 85 healthy controls) and lastly in 102 patients with MDD to identify possible overlapping and opposing effects of wLE on DNAm. Additionally, analysis of differentially methylated regions (DMRs) was conducted to identify regional clusters of association. Results: Two CpG-sites presented with p-values below 1x10-05 in PD: cg09738429 (p=6.40x10-06, located in an intergenic shore region in next proximity of PYROXD1) and cg03341655 (p=8.14x10-06, located in the exonic region of GFOD2). The association of DNAm at cg03341655 and wLE could be replicated in the independent MDD case sample indicating a diagnosis independent effect. Genes mapping to the top hits were significantly upregulated in brain and top hits have been implicated in the metabolic system. Additionally, two significant DMRs were identified for PD only on chromosome 10 and 18, including CpG-sites which have been reported to be associated with anxiety and other psychiatric phenotypes. Conclusion: This first DNAm analysis in PD reveals first evidence of small but significant DNAm changes in PD in association with cumulative stress-weighted life events. Most of the top associated CpG-sites are located in genes implicated in metabolic processes supporting the hypothesis that environmental stress contributes to health damaging changes by affecting a broad spectrum of systems in the body.

Genome wide DNA methylation profiling in the whole blood samples of healthy controls and major depression disorder (MDD) patients who have never been treated with depression medication. The Illumina Infinium 450k Human DNA methylation Beadchip can assay over 480K CpG sites with bisulfite-converted genomic DNA and has been widely used in methylome-wide association studies (MWAS). Samples included 40 healthy controls and 40 MDD patients who have never been treated with depression medication.

This pioneering study investigated associations between DNA methylation levels and PDB severity. 100 methylation sites associated with PDB disease severity were identified, while important molecular pathways associated with disease progression were also disclosed. Importantly, DNA methylation markers to predict disease severity with high accuracy were also identified but require further validations.

This study included whole-genome DNA methylation data from 64 whole-blood samples from patients recruited from the Hospital Psiquiatrico Infantil Juan N. Navarro in Mexico City. The project explored epigenetic changes associated with eating disorders in children and adolescents from a Mexican population.

To identified the differential methylation of genes and regions to elucidate the mechanisms of toxicity related to environmental chromium exposure. Fasting whole blood samples were collected by clinicians in ethylenediaminetetraacetic acid (EDTA) anticoagulant tubes, and stored them at −80 °C. A DNeasy Blood and Tissue Kit (Qiagen) was used to isolate DNA from whole blood. The purity and concentration of DNA were estimated using Nanodrop 2000 (ThermoScietific). Approximately 500 ng of genomic DNA from each sample was used for sodium bisulfite conversion with the EZ DNA methylation Gold Kit (Zymo Research, USA) in accordance with the manufacturer’s standard protocol. Genome-wide DNA methylation was performed using the Illumina Infinium HumanMethylation850K (EPIC) BeadChip (Illumina Inc, USA) in accordance with the manufacturer’s instructions.

Methylmercury (MeHg) is an environmental pollutant of global public health concern. MeHg is associated with immune dysfunction but the underlying mechanisms are unclear. The most common route of MeHg exposure is through consumption of fatty fish that contain beneficial n-3 polyunsaturated fatty acids (PUFA) that may protect against MeHg toxicity. To better inform individual costs and benefits of fish consumption, we aimed to identify candidate epigenetic biomarkers of biological responses that reflect MeHg toxicity and PUFA protection.

Adriatic islanders have a high prevalence of metabolic syndrome that is not fully explained by previous behavioral, dietary, and genetic studies. Some DNA methylation remains stable and may be established in early life, whereas others are dynamic and may vary over time in response to different conditions. The objective of the present study was to identify stable and dynamic DNA methylation loci associated with cardiometabolic traits among the populations from the island of Hvar, the largest island in the eastern Adriatic coast. An epigenome-wide association study (EWAS) was conducted using peripheral blood that was longitudinally collected at two time points, 10 years apart. DNA methylation was analyzed via Infinium MethylationEPIC BeadArray. Stable and dynamic loci were identified using linear mixed models. A total of 43,041 loci were classified as stable, while 45,769 loci were classified as dynamic. Associations between various cardiometabolic traits and stable and dynamic methylation loci were respectively assessed using linear mixed effects models adjusted for age, sex, and smoking status. After adjustment for false-discovery rate, 24 CpG loci were significantly associated with systolic blood pressure (Q < 0.1), of which 22 were stable loci and 2 were dynamic loci; while 12/22 (55%) of the systolic blood-pressure-associated stable loci resided in a gene promoter. Additionally, there was one stable locus associated with serum calcium and one with C-reactive protein. The results suggest that multiple genes involved in the determination of systolic blood pressure may be regulated via epigenetic programming established in early life.

Neuroepigenetics considers genetic sequences and the interplay with environmental influences to elucidate vulnerability risk for various neurological and psychiatric disorders. However, evaluating DNA methylation of brain tissue is challenging owing to the issue of tissue specificity. Consequently, peripheral surrogate tissues were used, resulting in limited progress compared with other epigenetic studies, such as cancer research. Therefore, we developed databases to establish correlations between the brain and peripheral tissues in the same individuals. Four tissues, resected brain tissue, blood, saliva, and buccal mucosa (buccal), were collected from 19 patients (aged 13–73 years) who underwent neurosurgery. Moreover, their genome-wide DNA methylation was assessed using the Infinium HumanMethylationEPIC BeadChip arrays to determine the cross-tissue correlation of each combination. These correlation analyses were conducted with all methylation sites and with variable CpGs, and with when these were adjusted for cellular proportions. For the averaged data for each CpG across individuals, the saliva–brain correlation (r = 0.90) was higher than that for blood–brain (r = 0.87) and buccal–brain (r = 0.88) comparisons. Among individual CpGs, blood had the highest proportion of CpGs correlated to the brain at nominally significant levels (19.0%), followed by saliva (14.4%) and buccal (9.8%). These results were similar to the previous IMAGE-CpG results; however, the correlation analysis between the correlation coefficients of the datasets revealed a relatively low degree of correlation (brain vs. blood: r = 0.27, saliva; r = 0.18, and buccal; r = 0.24). To the best of our knowledge, this is the fourth study in the literature initiating the development of databases for correlations between the brain and peripheral tissues in the same individuals. We present the first database developed from an Asian population, specifically Japanese samples (AMAZE-CpG), which would contribute to interpreting individual epigenetic study results from various Asian populations.

Background. Previous epigenome-wide association studies have shown that HIV infection can disrupt the host DNA methylation landscape. However, it remains unclear how antiretroviral therapy (ART) affects the HIV-induced epigenetic modifications. Methods. 184 individuals with HIV from the NEAT001/ANRS143 clinical trial (with pre-ART and post-ART samples [96 weeks of follow-up]) and 44 age-and-sex matched individuals without HIV were included. We compared genome-wide DNA methylation profiles in whole blood between groups adjusting for age, sex, batch effects, and leucocyte type heterogeneity. Findings. We identified 430 differentially methylated positions (DMPs) between HIV+ pre-ART individuals and HIV-uninfected controls. In participants with HIV, ART initiation modified the DNA methylation levels at 845 CpG positions and restored 49.3% of the changes found between HIV+ pre-ART and HIV-uninfected individuals. We only found 15 DMPs when comparing DNA methylation profiles between HIV+ post-ART individuals and participants without HIV. The Gene Ontology enrichment analysis of DMPs associated with untreated HIV infection revealed an enrichment in biological processes regulating the immune system and antiviral responses. In participants with untreated HIV infection, DNA methylation levels at top HIV-related DMPs were associated with CD4/CD8 ratios and viral loads. Changes in DNA methylation levels after ART initiation were weakly correlated with changes in CD4+ cell counts and the CD4/CD8 ratio. Interpretation. Control of HIV viraemia after 96 weeks of ART initiation restores most of the host DNA methylation changes that occurred before antiretroviral treatment of HIV infection.

Methylation profiles from blood samples of participants in the COVID-19 Health Action Response for Marines (CHARM) study were generated to study innate immune responses to SARS-CoV-2 infection. We investigate (1) methylome changes after infection; (2) methylation site dynamics; (3) a methylation-based clock that enables accurate time since infection predictions following acute SARS-CoV-2 and (4) Immunological effects of methylation pattern and relations to other conditions.

Black and Hispanic American patients frequently develop earlier onset of multiple sclerosis (MS) and a more severe disease course that can be resistant to disease modifying treatments. The objectives were to identify differential methylation of genomic DNA (gDNA) associated with disease susceptibility and treatment responses in a cohort of MS patients from underrepresented minority populations. Patients with MS and controls with non-inflammatory neurologic conditions were consented and enrolled under an IRB-approved protocol. Approximately 64% of donors identified as Black or African American and 30% as White, Hispanic-Latino. Infinium MethylationEPIC bead arrays were utilized to measure epigenome-wide gDNA methylation of whole blood. Data were analyzed in the presence and absence of adjustments for unknown covariates in the dataset, some of which corresponded to disease modifying treatments. Global patterns of differential methylation associated with MS were strongest for those probes that showed relative demethylation of loci with lower M values. Pathway analysis revealed unexpected associations with shigellosis and amoebiasis. Enrichment analysis revealed an over-representation of probes in enhancer regions and an under-representation in promoters. In the presence of adjustments for covariates that included disease modifying treatments, analysis revealed 10 differentially methylated regions (DMR’s) with an FDR <1E-77. Five of these genes (ARID5B, BAZ2B, RABGAP1, SFRP2, WBP1L) are associated with cancer risk and cellular differentiation and have not been previously identified in MS studies. Hierarchical cluster and multi-dimensional scaling analysis of differential DNA methylation at 147 loci within those DMR’s was sufficient to differentiate MS donors from controls. In the absence of corrections for disease modifying treatments, differential methylation in patients treated with dimethyl fumarate was associated with immune regulatory pathways that regulate cytokine and chemokine signaling, axon guidance, and adherens junctions. These results demonstrate possible associations of gastrointestinal pathogens and regulation of cellular differentiation with MS susceptibility in our patient cohort. This work further suggests that analyses can be performed in the presence and absence of corrections for immune therapies. Because of their high representation in our patient cohort, these results may be of specific relevance in the regulation of disease susceptibility and treatment responses in Black and Hispanic Americans.

Whole blood methylomics, transcriptomics and plasma proteomics were obtained for 391 participants of the Progression of Early Subclinical Atherosclerosis (PESA) study. Epigenetic age was calculated from methylomics data for each participant. Its divergence from chronological age is termed epigenetic age acceleration. Subclinical atherosclerosis burden was estimated by multi-territory 2D/3D vascular ultrasound and by coronary artery calcification.

Aicardi-Goutières Syndrome (AGS) is a rare neuro-inflammatory disease characterized by increased expression of interferon-stimulated genes (ISGs). Disease-causing mutations are present in genes associated with innate antiviral responses. Disease presentation and severity vary, even between patients with identical mutations from the same family. This study investigated DNA methylation signatures in PBMCs to understand phenotypic heterogeneity in AGS patients with mutations in RNASEH2B. AGS patients presented hypomethylation of ISGs and differential methylation patterns (DMPs) in genes involved in “neutrophil and platelet activation”. Patients with “mild” phenotypes exhibited DMPs in genes involved in “DNA damage and repair”, whereas patients with “severe” phenotypes had DMPs in “cell fate commitment” and “organ development” associated genes. DMPs in two ISGs (IFI44L, RSAD2) associated with increased gene expression in patients with “severe” when compared to “mild” phenotypes. In conclusion, altered DNA methylation and ISG expression as biomarkers and potential future treatment targets in AGS. This project aimed at testing the hypothesis that DNA methylation may influence gene expression, thereby affecting associated clinical phenotypes in AGS patients with the same mutation (RNASEH2B p.A177T).

The majority (72%) of adolescents with myelodysplastic syndrome and monosomy 7 carry an underlying GATA2 deficiency. Nowadays, chemotherapy and allogenic hematopoietic stem cell transplantation (HSCT) are the only cure, pointing out the urgent need to develop reliable predictive tools. Familial cases carrying the same mutation in the GATA2 gene develop the disease at different age. The trigger of the disease is still unknown. Therefore, it is needed to understand the genetic mechanisms (mutations) and epigenetic mechanism, such as, DNA methylation, a cellular mechanism to control gene expression. Abnormal DNA methylation has been linked to several adverse outcomes, including human diseases. In this study, we deeply characterized 20 Spanish GATA2 deficient patients; study the presence of secondary mutations, clinical phenotype and DNA methylation. We have found that the most frequent secondary mutations are in STAG2 and ASXL1 genes, detected in 30% and 20% of the patients, respectively, a similar ratio has been described in a bigger cohort, showing that our 20-patient cohort is representative of the GATA2 deficiency scenario. For the first time, we found a specific hypermethylated signature in GATA2 patients, opening a novel point of view in the GATA2-patient diagnostic and facilitating the risk estimation of themselves. Furthermore, whether the methylation profiling is accurate enough, it will be useful to predict the onset of the disease progression.

Genome-wide DNA methylation profiling of venous blood samples from children in the Eastern Democratic Republic of Congo from birth to age three. DNA methylation data were noob normalized and uploaded to Steve Horvath's epigenetic age calculator website to calculate Horvath epigenetic age acceleration for each participant at each timepoint for which they had data available. Replicates were averaged and a single outlier at birth was removed as described in the manuscript, leaving 155 observations from 67 unique individuals. Sample size at each timepoint was as follows: n = 64 at birth, n = 8 at six months, n= 35 at one year, n = 32 at two years, and n = 16 at three years.

Aging is classically conceptualized as an ever-increasing trajectory of damage accumulation and loss of function, leading to increases in morbidity and mortality. However, recent in vitro studies have raised the possibility of age reversal. We characterized several models in which biological age, assessed primarily through analysis of DNA methylation, undergoes reversible changes. Severe COVID-19 is one such example.

Given the salient role of early-life adversity and the resulting biological embedding in disease risk, there is a critical need to understand the mechanisms operating at multiple levels of analysis in order to promote effective clinical treatments and intervention efforts for survivors. An example for such an effort could be to utilize models of dynamic cellular markers as individual-level factors to account for variation in intervention response and clinical outcomes. Results of this study will lead to new knowledge about specific gene expression pathways in response to stress, and whether the response is moderated by previous exposure to early adversity, shorter telomere length (a marker of cellular aging) and self-report mental-health measures. Thus, the long-term effects of this study will advance our understanding on stress-related transcriptomic changes that play a downstream role in disease susceptibility and accelerated aging, with the goal of targeting specific pathways and genes for potential intervention studies and pharmacological treatments to reverse the effects of exposure to early adversity. For example, considering high failure rates for depression treatments, and in order to tailor individual interventions, identifying objective changes in stress-induced gene expression may help to predict intervention efficacy in clinical and non-clinical settings, as seen, for example, in breast and leukemia cancers. Thus, findings will have a range of impacts for basic science, intervention studies and clinical practice that will influence treatments to match the specific cellular processes operating within an individual.

Although Leflunomide (LEF) is effective in treating rheumatoid arthritis (RA), there are still a considerable number of patients who respond poorly to LEF treatment. Till date, few LEF efficacy-predicting biomarkers have been identified. Herein, we explored and developed a DNA methylation-based predictive model for LEF-treated RA patient prognosis.

Lobachevsky University DNAm dataset. Whole blood DNA Methylation (EPIC) profiles from healthy samples from two regions: central Russia (131 samples) and Yakutia (114 samples) obtained in the Laboratory of System Medicine for Healthy Aging, Lobachevsky State University of Nizhny Novgorod, Russia Dataset contains DNAm data from 245 healthy control samples from two regions: central Russia (131) and Yakutia (114). The following characteristics are available for all samples: sex, age, region. Healthy participants in the central Russia region were recruited in 2019–2022. Yakutian participants we recruited in 2022. All measurements were performed at the Laboratory of System Medicine for Healthy Aging, Lobachevsky State University of Nizhny Novgorod, Russia.

We assessed DNA methylation in whole blood samples from an Australian population across different age groups. Our study focused on evaluating the accuracy of DNA methylation age estimation using the Horvath 2018 and PhenoAge clocks. Additionally, we examined previously reported functional measures of aging in peripheral blood mononuclear cells (PBMCs). Our findings indicated that DNA methylation age effectively predicted donor age, while only a limited number of tested cell functions showed correlations with donor age.

Background: Bladder cancer and therapy responses hinge on immune profiles in the tumor microenvironment (TME) and blood, yet studies linking tumor-infiltrating immune cells to peripheral immune profiles are limited. Methods: DNA methylation cytometry quantified TME and matched peripheral blood immune cell proportions. With tumor immune profile data as the input, subjects were grouped by immune infiltration status and consensus clustering. Results: Immune hot and cold groups had different immune compositions in the TME but not in circulating blood. Two clusters of patients identified with consensus clustering had different immune compositions not only in the TME but also in blood. Conclusions: Detailed immune profiling via methylation cytometry reveals the significance of understanding tumor and systemic immune relationships in cancer patients.

Child maltreatment (CM) is associated with adverse physical, psychological, and neurodevelopmental outcomes later in life. Epigenetic modifications, particularly DNA methylation, have been proposed as potential mechanisms underlying these long-term effects. To identify robust CM-associated methylation signatures, we conducted epigenome-wide analyses across three independent cohorts: judicial autopsy cases (CM:11, Controls:7), toddlers shortly after social intervention (CM:36, Controls:49), and adolescents who underwent brain MRI (CM:61, Controls:62). Each cohort was analyzed separately, followed by a meta-analysis to identify common methylation sites associated with CM exposure. The meta-analysis identified four significant CpG sites located within the ATE1, SERPINB9P1, CHST11, and FOXP1 genes. Among these, methylation of FOXP1 was consistently associated with structural brain alterations, including increased gray matter volume (GMV) in the orbitofrontal cortex (OFrC) and middle/posterior cingulate gyrus (MPCG), and decreased GMV in the occipital fusiform gyrus (OFuG). These brain regions are implicated in emotional regulation, memory retrieval, and social cognition, suggesting a potential neurobiological mechanism linking CM to later psychopathology. Furthermore, methylation risk scores (MRS) derived from these four CpGs successfully discriminated individuals who experienced early-life adversity in an independent validation dataset, achieving an area under the receiver operating characteristic curve (AUC) of 0.672, highlighting their potential utility as biomarkers. Gene ontology and pathway analyses revealed enrichment of cholinergic and glutamatergic synaptic transmission pathways, supporting their involvement in traumatic memory formation. Our findings provide novel insights into the epigenetic mechanisms underlying CM and identify potential biomarkers for early detection, prevention, and therapeutic intervention, ultimately contributing to breaking the intergenerational cycle of maltreatment.

Whole blood, stool samples, and questionnaire data were collected from participants in the DRIFT2 trial at baseline and at a 3 month follow-up visit to analyze relationships between DNA methylation, gut microbes, and diet data. 128 total whole blood samples were collected .

In this study, 60 post-mortem tissue samples comprising three tissue types (blood, brain, and heart) were collected from autopsies of 20 Koreans aged 18 to 78. 250 ng of genomic DNA (gDNA) was employed to generate DNA methylation profiles utilizing the Illumina Infinium MethylationEPIC BeadChip array (Illumina, San Diego, CA, USA) at Macrogen Inc. (Macrogen, Seoul, Korea).

DNA methylation microarrays have become a widely used tool for investigating epigenetic modifications in various aspects of biomedical research. However, technical variability in methylation data poses challenges for downstream applications such as predictive modeling of health and disease. In this study, we measure the impact of common sources of technical variability in Illumina DNA methylation microarray data, with a specific focus on positional biases inherent within the microarray technology. By utilizing a dataset comprised of multiple, highly similar technical replicates, we identified a chamber number bias, with different chambers of the microarray exhibiting systematic differences in fluorescence intensities and their derived methylation beta values, which are only partially corrected for by existing preprocessing methods, and demonstrate that this positional bias can lead to false positive results during differential methylation testing. Additionally, our investigation identified outliers in low-level fluorescence data which might play a role in contributing to predictive error in computational models of health-relevant traits such as age.

Epigenetic clocks are age predictors that use machine-learning models trained on DNA CpG methylation values to predict chronological or biological age. Increases in predicted epigenetic age relative to chronological age (epigenetic age acceleration) are connected to aging-associated pathologies, and changes in epigenetic age are linked to canonical aging hallmarks. However, epigenetic clocks rely on training data from bulk tissues whose cellular composition changes with age. We found that human naive CD8+ T cells, which decrease during aging, exhibit an epigenetic age 15–20 years younger than effector memory CD8+ T cells from the same individual. Importantly, homogenous naive T cells isolated from individuals of different ages show a progressive increase in epigenetic age, indicating that current epigenetic clocks measure two independent variables, aging and immune cell composition. To isolate the age-associated cell intrinsic changes, we created a new clock, the IntrinClock, that did not change among 10 immune cell types tested. IntrinClock showed a robust predicted epigenetic age increase in a model of replicative senescence in vitro and age reversal during OSKM-mediated reprogramming

Cannabis use has been controversial, largely having been designated a controlled substance over the last century. The link between cannabis smoking and disease pathogenesis may best be explored through DNA methylation, an epigentic mechanism. We investigated the relationship between epigenetic age and cannabis smoking in participants within the Canadian Cohort of Obstructive Lung Disease (CanCOLD) cohort (n=93) (ClinicalTrials.gov identifier NCT00920348). Blood samples were profiled for DNA methylation using the Illumina MethylationEPIC BeadChipv1 at two separate laboratories and the blood epigenetic age of each sample was calculated using the Clock Foundation tool (https://dnamage.clockfoundation.org). An ANOVA was used to identify differences in the age acceleration residuals associated with cannabis smoking status (never, former, and current), adjusted for chronological age, sex, body mass index (BMI), batch, cigarette smoking status, and the first two principal components of blood cell proportions. Our observations indicated that current cannabis smoking and higher joint-years exposure are associated with epigenetic age acceleration; cessation, however, may help to normalize in part this age acceleration.

Tissue biomarkers for immune checkpoint inhibitor (ICI) response are limited by tumor sample heterogeneity and availability. This study identifies clinically actionable pretreatment blood biomarkers that are associated with ICI treatment response and survival in recurrent/metastatic head and neck squamous cell carcinoma. A prospective multi-center study enrolled 100 patients before standard-of-care immunotherapy. Blood immune profiles, measured by methylation cytometry, were assessed alongside tumor mutational burden (TMB) and PD-L1 combined proportion score (CPS). TMB and PD-L1 CPS were available for 56 and 91 patients, respectively. High neutrophils, monocytes, and neutrophil-to-lymphocyte ratio were associated with worse survival, while high CD4T cells, especially naïve CD4T cells, and lymphocyte-to-monocyte ratio were associated with better survival. Significant interactions between TMB and peripheral immune profiles for both progression-free and overall survival were found. Clinically relevant pretreatment peripheral immune biomarkers were identified, demonstrating the potential of DNA-based immune profiling to predict ICI response before treatment.

Primary myelofibrosis (PMF) is a clonal blood disorder linked to mutually exclusive mutations in JAK2, CALR, or MPL genes. To understand the epigenetic effects of these mutations, we analyzed DNA methylation (DNAm) profiles of PMF patients. Notably, no differences were found between JAK2 and CALR mutated cases, whereas MPL mutations showed distinct DNAm patterns. Further investigation in induced pluripotent stem cell (iPSC) models with JAK2 mutations revealed only a moderate link to PMF-related epigenetic changes, suggesting these alterations are not directly caused by the mutations. Additionally, PMF-associated epigenetic changes showed minimal correlation with allele burden and were largely evoked by changes in the cellular composition. When comparing PMF DNAm profiles with those from other myeloid malignancies, such as acute myeloid leukemia, juvenile myelomonocytic leukemia, and myelodysplastic syndrome, many overlapping changes were found, making it difficult to distinguish PMF based on individual CpGs. However, a PMF score created by combining five CpGs successfully differentiated PMF from other diseases in training and validation datasets. These findings demonstrate that PMF driver mutations do not directly evoke epigenetic changes. While PMF shares epigenetic changes with other myeloid malignancies, epigenetic signatures can effectively differentiate PMF from related diseases.

Primary myelofibrosis (PMF) is a clonal blood disorder linked to mutually exclusive mutations in JAK2, CALR, or MPL genes. To understand the epigenetic effects of these mutations, we analyzed DNA methylation (DNAm) profiles of PMF patients. Notably, no differences were found between JAK2 and CALR mutated cases, whereas MPL mutations showed distinct DNAm patterns. Further investigation in induced pluripotent stem cell (iPSC) models with JAK2 mutations revealed only a moderate link to PMF-related epigenetic changes, suggesting these alterations are not directly caused by the mutations. Additionally, PMF-associated epigenetic changes showed minimal correlation with allele burden and were largely evoked by changes in the cellular composition. When comparing PMF DNAm profiles with those from other myeloid malignancies, such as acute myeloid leukemia, juvenile myelomonocytic leukemia, and myelodysplastic syndrome, many overlapping changes were found, making it difficult to distinguish PMF based on individual CpGs. However, a PMF score created by combining five CpGs successfully differentiated PMF from other diseases in training and validation datasets. These findings demonstrate that PMF driver mutations do not directly evoke epigenetic changes. While PMF shares epigenetic changes with other myeloid malignancies, epigenetic signatures can effectively differentiate PMF from related diseases.

Epigenetic clocks are a common group of tools used to measure biological aging – the progressive deterioration of cells, tissues and organs. Epigenetic clocks have been trained almost exclusively using blood-based tissues but there is growing interest in estimating epigenetic age using less-invasive oral-based tissues (i.e., buccal or saliva) in both research and commercial settings. However, differentiated cell types across body tissues exhibit unique DNA methylation landscapes and age-related alterations to the DNA methylome. Applying epigenetic clocks derived from blood-based tissues to estimate epigenetic age of oral-based tissues may introduce biases. We tested the within-person comparability of common epigenetic clocks across four tissue types: buccal epithelial, saliva, dry blood spots, and peripheral blood mononuclear cells. We tested 163 distinct tissue samples from 47 individuals aged 19-70 years. Overall, there were significant within-person differences in epigenetic clock estimates from oral-based versus blood-based tissues, with average differences of almost 30 years observed in some age clocks. In addition, most epigenetic clock estimates of blood-based tissues exhibited low correlation with estimates from oral-based tissues despite controlling for cellular proportions and other technical factors. Notably, the Skin and Blood clock exhibited the lowest age acceleration values of any clock across all tissue types, indicating its unique ability to accurately estimate chronological age in both oral- and blood-based tissues. Our findings indicate that application of blood-derived epigenetic clocks in oral-based tissues may not yield comparable estimates of epigenetic age, highlighting the need for careful consideration of tissue type when estimating epigenetic age. NOTE: The full study included children and adult samples, however, the current data only includes the adult samples (sample sizes and age range have been adjusted to reflect the adult data only).

Background and Aims: Metabolic liver disease is the fastest rising cause of hepatocellular carcinoma (HCC) worldwide, but the underlying molecular processes that drive HCC development in the setting of metabolic perturbations are unclear. We investigated the role of aberrant DNA methylation in metabolic HCC development in a multicenter international study. Results: We enrolled 272 metabolic HCC patients and 316 control patients with metabolic liver disease from six sites. Fifty-five differentially methylated CpGs were identified; 33 hypermethylated and 22 hypomethylated in cases versus controls. The panel of 55 CpGs discriminated between cases and controls with AUC=0.79 (95%CI=0.71-0.87), sensitivity=0.77 (95%CI=0.66-0.89), and specificity=0.74 (95%CI=0.64-0.85). The 55-CpG classifier panel performed better than a base model that comprised age, sex, race, and diabetes mellitus (AUC=0.65, 95%CI=0.55-0.75, sensitivity=0.62 (95%CI=0.49-0.75) and specificity=0.64 (95%CI=0.52-0.75). A multifactorial model that combined the 55 CpGs with age, sex, race, and diabetes, yielded AUC=0.78 (95%CI=0.70-0.86), sensitivity=0.81 (95%CI=0.71-0.92), and specificity=0.67 (95%CI=0.55-0.78). Conclusions: A panel of 55 blood leukocyte DNA methylation markers differentiates patients with metabolic HCC from control patients with benign metabolic liver disease, with a slightly higher sensitivity when combined with demographic and clinical information.

Genome-wide DNA methylation profiling of blood samples from people living with HIV HIV-1 infection impacts biological ageing, and epigenetic clocks highlight epigenetic age acceleration in people with HIV. Despite evidence indicating sex differences in clinical, immunological, and virological measures, females have been underrepresented in most HIV epigenetic studies. Hence, we generated a more representative epigenetic dataset to examine sex differences in epigenetic ageing and relationships to clinical phenotypes.

The recently launched Illumina Infinium MethylationEPIC v2.0 (EPICv2), successor of MethylationEPIC v1.0 (EPICv1), retains a majority of probes in EPICv1, while expanding coverage of regulatory elements. The concordance between the two EPIC versions in DNA methylation-based tools has not yet been investigated. To address this, DNA methylation was profiled on both versions using matched blood samples across four cohorts spanning early to late adulthood. High concordance between versions at the array level but variable agreement at the individual probe level was noted. A significant contribution of EPIC version to DNA methylation variation was observed, though it was to a smaller extent compared to sample relatedness and cell type composition. Modest but significant differences in DNA methylation-based estimates between versions were observed, irrespective of the data preprocessing method used. Adjustments for EPIC version or calculation of estimates separately for each version largely mitigated these version-specific discordances. This work emphasizes the importance of accounting for EPIC version differences in research scenarios, especially in meta-analyses and longitudinal studies that require data harmonization across versions.

This study is part of an investigation into the differential gene expression and methylation patterns in response to sub-anaesthetic oral ketamine treatment of PTSD to identify key molecular markers in building a predictive profile in determining longer term treatment outcomes. The data from this study is included in a number of articles and highlights the utility of combining gene expression data with epigenetic data and clinical outcomes to elucidate molecular profils receptive to ketamine’s sustained therapeutic effects as a step towards precision medicine.

The lifestyle patterns of top athletes are highly disciplined, featuring strict exercise regimens, nutrition plans, and mental preparation, often beginning at a young age. Recently, it was shown that physically active individuals exhibit slowed epigenetic aging and better age-related outcomes. Here, we investigate whether the extreme intensity of physical activity of Olympic champions still has a beneficial effect on epigenetic aging. To test this hypothesis, we examined the epigenetic aging of 59 Hungarian Olympic champions and of the 332 control subjects, 205 were master rowers. We observed that Olympic champions exhibit slower epigenetic aging, applying seven state-of-the-art epigenetic aging clocks. Additionally, male champions who won any medal within the last 10 years showed slower epigenetic aging compared to other male champions, while female champions exhibited the opposite trend. We also found that wrestlers had higher age acceleration compared to gymnasts, fencers, and water polo players. We identified the top 20 genes that showed the most remarkable difference in promoter methylation between Olympic champions and non-champions. The hypo-methylated genes are involved in synaptic health, glycosylation, metal ion membrane transfer, and force generation. Most of the hyper-methylated genes were associated with cancer promotion. The data suggest that rigorous and long-term exercise from adolescence to adulthood has beneficial effects on epigenetic aging.

Background: Obesity, a health concern shaped by genetic, epigenetic, and environmental factors, has emerged as a global epidemic, particularly with a 60% increment in Brazil from 2006 to 2016. This study explored the effects of an 8-week integrated strength and aerobic training protocol on the DNA methylation patterns in 11 sedentary women with obesity

Thymic involution is an age-related process that results in reduced T cell production and impaired adaptive immunity. However, it remains uncertain the extent of thymic activity later in life and how this contributes to immunological ageing. Here, we identified thymic tissue within mediastinal adipose locations in aged individuals and confirmed its functional capacity through multi-omics analysis. Percentage of CD31+ CD4+ T cells correlated positively with thymic tissue presence. Thymic output in elderly showed a high degree of heterogeneity was modulated by gender and smoking history. Thymus activity was associated with a diverse TCR repertoire, unique transcriptomic profile, and distinct epigenetic signature. Adipose tissue inflammation was found to be independent of thymic activity but associated with the presence of circulating T cells with an immunosenescent phenotype. Further analysis revealed functional and phenotypic heterogeneity within distinct naïve CD4 T cell subsets, which are influenced by thymic activity.

Peripheral blood DNA methylation was profiled in 46 patients with treatment-resistant depression prior to treatment with transcranial magnetic stimulation (TMS). Genome-wide DNA methylation was measured using the Illumina Infinium MethylationEPIC BeadChip (850K array). Following quality control, data from 46 subjects were included in downstream analyses. Treatment outcomes were assessed using the PHQ-9 depression scale and included treatment response (≥50% reduction in PHQ-9), symptom trajectory (ΔPHQ-9), and remission (PHQ-9 score < 5). Methylation data were analyzed to identify differentially methylated regions (DMRs) associated with treatment outcomes. Both raw IDAT files and processed beta-value data are provided.

Epigenetic alterations, particularly DNA methylation, are recognized as robust biomarkers of ageing and have been associated with conditions such as obesity and sarcopenia. When these two conditions coexist, the result is sarcopenic obesity (SO), a functional and clinical condition characterized by excess fat mass and reduced muscle mass and function. Although cross-talk between muscle and fat tissue is thought to play a central role in SO pathophysiology, the epigenetic mechanisms involved remain poorly understood. Thus, this study aimed to investigate whole-blood DNA methylation patterns in older women with sarcopenic obesity, obesity, sarcopenia, and normal weight, as well as to explore the associated signaling pathways.

Many survivors of acute lymphoblastic leukemia (ALL) develop late effects that include lifelong impairments in cognitive function. We examined DNA methylation (DNAm) patterns in healthy blood from two independent cohorts of ALL survivor to 1) identify distinct genome-wide DNAm alterations (signatures) in survivors, and establish long-term epigenetic dysregulation as a common outcome of ALL treatment, and 2) elucidate the role of epigenetics as a biomarker and potential mechanism of neurocognitive deficits in ALL survivors. We identified a signature of 452 CpG sites in the blood of ALL survivors vs. controls, that demonstrated ~99% sensitivity and 85% specificity, irrespective of time elapsed from the end of treatment. Using St. Jude LIFE as a validation cohort, we found that survivors of non-ALL childhood cancers carried a different DNAm signature. Finally, we found 43 distinct CpGs associated with neurocognitive deficits as defined by the neuropsychological test, DIVERGT, that replicated across our two cohorts of ALL survivors. We propose DNAm as a potential biomarker that could predict patients most likely to experience neurocognitive deficits following ALL treatment and inform early interventions.

Many survivors of acute lymphoblastic leukemia (ALL) develop late effects that include lifelong impairments in cognitive function. We examined DNA methylation (DNAm) patterns in healthy blood from two independent cohorts of ALL survivor to 1) identify distinct genome-wide DNAm alterations (signatures) in survivors, and establish long-term epigenetic dysregulation as a common outcome of ALL treatment, and 2) elucidate the role of epigenetics as a biomarker and potential mechanism of neurocognitive deficits in ALL survivors. We identified a signature of 452 CpG sites in the blood of ALL survivors vs. controls, that demonstrated ~99% sensitivity and 85% specificity, irrespective of time elapsed from the end of treatment. Using St. Jude LIFE as a validation cohort, we found that survivors of non-ALL childhood cancers carried a different DNAm signature. Finally, we found 43 distinct CpGs associated with neurocognitive deficits as defined by the neuropsychological test, DIVERGT, that replicated across our two cohorts of ALL survivors. We propose DNAm as a potential biomarker that could predict patients most likely to experience neurocognitive deficits following ALL treatment and inform early interventions.

DNA methylation is tissue specific, which has profound implications for data analysis. While both capillary and venous blood samples are whole blood, they are not identical in their clinical profiles. Here we assess the congruency of DNA methylation from 20 individuals with matched venous and capillary blood draw DNA methylation. We used DNA methylation profiles from Illumina EPIC v2 arrays assess the differences of these blood sources in quality control approches, in predicted immune cell proportions, in DNA methylation based predictors including epigenetic clocks and lifestyle predictors, and performed an examplar EWAS

Long-term survivors of childhood cancer experience treatment-related cardiotoxicity among a broad spectrum of chronic health conditions, which may be further aggrevated by suboptimal life-course social/behavioral/environmental exposures. Epigenetic mechanisms, particularly DNA methylation (DNAm), provide a potential link through which these exposures become biologically embedded and subsequently influence long-term health outcomes. Epigenome-wide association studies (EWAS) identified DNAm signatures associated with both treatment effects as well as life-course exposures. In parallel, DNAm variations were also evaluated in relation to cardiometabolic risk factors, cardiovascular diseases, and other chronic health conditions, revealing individual CpG sites or genes/geomic regions where these CpGs reside linked to clinically relevant phenotypes. Together, these findings support DNAm as a molecular interface connecting diverse exposures to adverse health outcomes. In addition, epigenetic age acceleration, assessed using DNAm-based aging biomarkers, was observed among survivors exposed to cancer treatments. Epigenetic age acceleration mediated a substantial proportion of the associations between cancer treatment exposures and cardiometabolic risk factors or cardiovascular diseases, supporting accelerated biological aging as a key pathway linking cancer treatment to long-term morbidity. Lifestyle and health behaviors, as well as social vulnerability and psychosocial stress, were also associated with variations in epigenetic age acceleration, highlighting the potential modifiability of aging-related pathways in ameliorating late-effects among childhood cancer survivors. In conclusion, these findings establish DNAm—captured through EWAS signatures and epigenetic age acceleration—as central molecular mechanisms linking treatment effects and life-course exposures to cardiotoxicity along with other chronic health conditions in childhood cancer survivors. This integrative epigenetic framework supports the use of DNAm-based biomarkers for risk stratification and nominates modifiable pathways as potential intervention targets to improve long-term survivorship outcomes.

The abundance, dynamics, and context-dependent heterogeneity of DNA methylation, where a pattern considered abnormal in one cell type may be normal in another, complicate the identification of early methylation changes that drive or signal disease development. This complexity can obscure early markers of increased disease risk, making it challenging to detect and intervene in disease processes at their inception. Here, we report 31,744 CpG sites exhibiting highly consistent methylation profiles in the blood of young, healthy individuals. We assess alterations at these epigenetically stable loci in 8,886 individuals across 29 diverse cohorts, including those with hematological cancers (n = 3,159), cardiovascular complications (n = 2,788), and healthy controls (n = 2,939). Our findings reveal methylation pattern disruption in myeloid and lymphoid malignancies, correlating with clonal burden dynamics and mutation frequency throughout leukemia treatment. In non-cancer cohorts, we observe that methylation levels at epigenetically stable loci become increasingly variable with age, a shift linked to higher cardiovascular disease risk and lower survival rates. This study highlights DNA methylation instability as a blood-based biomarker for both hematological cancer and cardiovascular disease and uncovers a mechanistic link between methylation dynamics and the expansion of maladaptive hematopoietic clones.

We aimed to further elucidate the role of dysregulated DNA methylation in Parkinson's disease and to evaluate the biomarker potential of methylation-based profiling. We conducted an epigenome-wide association study (EWAS) in whole blood, including 280 Parkinson's disease and 279 control participants from Oslo, Norway. Data were later meta-analysed with data from other sources. Methods: We conducted an epigenome-wide association study (EWAS) in whole blood, including 280 Parkinson's disease and 279 control participants from Oslo, Norway. The Illumina Infinium MethylationEPIC Beadchip was used to obtain DNA methylation profiles across approximately 850,000 CpGs in postmortem human frontal cortex samples from European donors in the Netherlands Brain Bank. Following quality checks, sample filtering and normalization, association between CpG methylation and Braak alpha-synuclein stage was assessed using linear models.

Background and Aims: Celiac disease (CeD) is an autoimmune disease triggered by dietary gluten in genetically predisposed individuals. Deamidation of gluten peptides by the CeD autoantigen and enzyme transglutaminase 2 (TG2) is central to the pathogenesis of CeD. Inhibition of TG2 with the specific inhibitor ZED1227 effectively prevents gluten-induced histological damage in CeD patients. Here we aimed to explore the blood DNA methylomic changes in ZED1227-treated CeD patients undergoing a gluten challenge. Results: Drug treatment revealed consistent patterns suggesting normalization of the DNA methylome indicating that ZED1227 attenuated the systemic responses to gluten challenge. Conclusions: These findings provide evidence that ZED1227 can significantly prevent the gluten-induced CeD-associated systemic changes. Clinical trial: EudraCT 2017-002241-30

Aims: Obesity is influenced by epigenetic mechanisms; however, little is known about DNA methylation markers associated with exercise-induced health-promotion interventions. This aims to explore the episignatures of an 8-week combined physical exercise training protocol on DNA methylation patterns in women with obesity. Patients and Methods: Thirteen women with obesity (BMI: 33 ± 2 kg/m²; age: 34 ± 5 years) underwent assessments of body composition, waist circumference, physical performance (VO₂max), and peripheral blood collection before and after an 8-week combined physical training intervention (3 sessions/week, 55 minutes/session, 70-90% maximum heart rate). DNA methylation was analyzed using the Illumina EPIC BeadChip. Results: The intervention improved clinical outcomes, including reduced waist circumference and increased VO₂max (p < 0.05). Epigenome-wide analysis identified 15 differentially methylated regions, highlighting hypomethylation in SLFN11 and PM20D1 hypermethylation in GATA5. These genes are involved in pathways related to immune response, tumor suppression, thermogenesis, metabolic regulation, adiposity, glucose homeostasis, and transcriptional control. Conclusion: Combined physical training induced clinical improvements and DNA methylation changes in women with obesity, suggesting that exercise may alter the episignatures related to obesity.

Delirium is a common yet underdiagnosed condition in elderly hospitalized patients. The lack of effective diagnostic and therapeutic methods can be attributed to the limited understanding of its pathophysiology. Delirium has recently been reported to be linked to neuroinflammation and epigenetic changes. The aim of this study was to validate the pathways in a larger cohort with a uniform type of surgery, while rigorously adjusting for potential covariates. This study primarily investigated DNA methylation (DNAm) changes before and after surgery in postoperative delirium (POD) among older adults having undergone femoral fracture surgery. After propensity analysis, 65 subjects were divided into 2 subgroups; one consisted of subjects who had blood samples collected preoperatively and on postoperative day 0, and the other consisted of those who had samples collected preoperatively and on postoperative day 3. We performed differential methylation analysis and enrichment analysis on each subgroup. Enrichment analysis using CpGs that exhibited substantial DNAm changes between pre- and postoperative day 0 samples in POD cases showed inflammation- and immunity-related pathways such as "leukocyte mediated immunity" and "NF-kappa B signaling pathway." Inflammation- and immunity-related pathways became less noticeable between pre- and postoperative day 3 samples. Inflammation- and immunity-related pathways showed in this study align with previous studies across diverse populations, reinforcing the role of inflammation- and immunity-related epigenetic mechanisms in delirium including POD. Notably, these DNAm changes were potentially transient, corresponding to the typical onset of delirium, suggesting their potential as biomarkers for early diagnosis.

Epigenetic aging clocks based on DNA methylation patterns across the genome have emerged as a potential biomarker for risk of age-related diseases, like Alzheimer's disease (AD), and environmental and social stressors. However, methylation clocks have not been comprehensively validated in genetically diverse individuals. Here we evaluate a set of first-, second-, and third-generation methylation clocks in 621 AD patients and matched controls from African American, Hispanic, and White cohorts. The clocks are less accurate at predicting age in genetically admixed cohorts compared to the White cohort, especially for those with substantial African ancestry. This decreased accuracy holds in >2,500 individuals of European and African ancestry from three additional datasets. The clocks also fail to consistently identify age acceleration in admixed AD cases compared to controls. To explore potential causes for the lack of generalization of the clocks, we intersected clock CpGs with methylation, germline genetic variants, and methylation QTL (meQTL) data from global populations. We find differential methylation between African and European ancestry individuals is common for clock CpGs. Genetic variants rarely disrupt clock CpGs between populations, but a substantial fraction of clock CpGs have meQTL with significantly higher frequencies in African genetic ancestries. Our results demonstrate that methylation clocks often fail to predict age and AD risk when applied across populations and suggest avenues for improving their portability by considering differences in genetic and epigenetic patterns across human populations.

Natural menopause marks the end of female reproductive capacity, yet its relationship with biological aging remains unclear. Earlier menopause has been associated with reduced lifespan and increased disease risk, but whether menopause itself accelerates aging or reflects an underlying faster biological aging trajectory remains unresolved. Here, we combined animal models of menopausal transition with epigenetic analyses in postmenopausal women, to investigate this relationship. In rats, neither surgically induced menopause nor natural reproductive senescence resulted in increased epigenetic age acceleration. In women, accelerated epigenetic aging was observed only in individuals who reached postmenopause earlier than the cohort median, independent of metabolic health status. Differential methylation analysis suggested an association between age at menopause and pathways involved in longevity, chromatin regulation, and neurodegeneration. Together, these findings support a model in which the timing of reproductive aging reflects systemic biological aging rather than directly driving it, positioning age at menopause as a potential biomarker of the rate of biological aging