1 3951 179 LOCUS-SPECIFIC DIFFERENTIAL DNA METHYLATION AND URINARY ARSENIC: AN EPIGENOME-WIDE ASSOCIATION STUDY IN BLOOD AMONG ADULTS WITH LOW-TO-MODERATE ARSENIC EXPOSURE. BACKGROUND: CHRONIC EXPOSURE TO ARSENIC (AS), A HUMAN TOXICANT AND CARCINOGEN, REMAINS A GLOBAL PUBLIC HEALTH PROBLEM. HEALTH RISKS PERSIST AFTER AS EXPOSURE HAS ENDED, SUGGESTING EPIGENETIC DYSREGULATION AS A MECHANISTIC LINK BETWEEN EXPOSURE AND HEALTH OUTCOMES. OBJECTIVES: WE INVESTIGATED THE ASSOCIATION BETWEEN TOTAL URINARY AS AND LOCUS-SPECIFIC DNA METHYLATION IN THE STRONG HEART STUDY, A COHORT OF AMERICAN INDIAN ADULTS WITH LOW-TO-MODERATE AS EXPOSURE [TOTAL URINARY AS, MEAN (+/-SD) MUG/G CREATININE: 11.7 (10.6)]. METHODS: DNA METHYLATION WAS MEASURED IN 2,325 PARTICIPANTS USING THE ILLUMINA METHYLATIONEPIC ARRAY. WE IMPLEMENTED LINEAR MODELS TO TEST DIFFERENTIALLY METHYLATED POSITIONS (DMPS) AND THE DMRCATE METHOD TO IDENTIFY REGIONS (DMRS) AND CONDUCTED GENE ONTOLOGY ENRICHMENT ANALYSIS. MODELS WERE ADJUSTED FOR ESTIMATED CELL TYPE PROPORTIONS, AGE, SEX, BODY MASS INDEX, SMOKING, EDUCATION, ESTIMATED GLOMERULAR FILTRATION RATE, AND STUDY CENTER. ARSENIC WAS MEASURED IN URINE AS THE SUM OF INORGANIC AND METHYLATED SPECIES. RESULTS: IN ADJUSTED MODELS, METHYLATION AT 20 CPGS WAS ASSOCIATED WITH URINARY AS AFTER FALSE DISCOVERY RATE (FDR) CORRECTION (FDR < 0.05). AFTER BONFERRONI CORRECTION, 5 CPGS REMAINED ASSOCIATED WITH TOTAL URINARY AS (PBONFERRONI < 0.05), LOCATED IN SLC7A11, ANKS3, LINGO3, CSNK1D, ADAMTSL4. WE IDENTIFIED ONE DMR ON CHROMOSOME 11 (CHR11:2,322,050-2,323,247), ANNOTATED TO C11ORF2; TSPAN32 GENES. DISCUSSION: THIS IS ONE OF THE FIRST EPIGENOME-WIDE ASSOCIATION STUDIES TO INVESTIGATE AS EXPOSURE AND LOCUS-SPECIFIC DNA METHYLATION USING THE ILLUMINA METHYLATIONEPIC ARRAY AND THE LARGEST EPIGENOME-WIDE STUDY OF AS EXPOSURE. THE TOP DMP WAS LOCATED IN SLC7A11A, A GENE INVOLVED IN CYSTINE/GLUTAMATE TRANSPORT AND THE BIOSYNTHESIS OF GLUTATHIONE, AN ANTIOXIDANT THAT MAY PROTECT AGAINST AS-INDUCED OXIDATIVE STRESS. ADDITIONAL DMPS WERE LOCATED IN GENES ASSOCIATED WITH TUMOR DEVELOPMENT AND GLUCOSE METABOLISM. FURTHER RESEARCH IS NEEDED, INCLUDING RESEARCH IN MORE DIVERSE POPULATIONS, TO INVESTIGATE WHETHER AS-RELATED DNA METHYLATION SIGNATURES ARE ASSOCIATED WITH GENE EXPRESSION OR MAY SERVE AS BIOMARKERS OF DISEASE DEVELOPMENT. HTTPS://DOI.ORG/10.1289/EHP6263. 2020 2 2921 59 GENE-SPECIFIC DIFFERENTIAL DNA METHYLATION AND CHRONIC ARSENIC EXPOSURE IN AN EPIGENOME-WIDE ASSOCIATION STUDY OF ADULTS IN BANGLADESH. BACKGROUND: INORGANIC ARSENIC IS ONE OF THE MOST COMMON NATURALLY OCCURRING CONTAMINANTS FOUND IN THE ENVIRONMENT. ARSENIC IS ASSOCIATED WITH A NUMBER OF HEALTH OUTCOMES, WITH EPIGENETIC MODIFICATION SUGGESTED AS A POTENTIAL MECHANISM OF TOXICITY. OBJECTIVE: AMONG A SAMPLE OF 400 ADULT PARTICIPANTS, WE EVALUATED THE ASSOCIATION BETWEEN ARSENIC EXPOSURE, AS MEASURED BY BLOOD AND URINARY TOTAL ARSENIC CONCENTRATIONS, AND EPIGENOME-WIDE WHITE BLOOD CELL DNA METHYLATION. METHODS: WE USED LINEAR REGRESSION MODELS TO EXAMINE THE ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND METHYLATION AT EACH CPG SITE, ADJUSTED FOR SEX, AGE, AND BATCH. DIFFERENTIALLY METHYLATED LOCI WERE SUBSEQUENTLY EXAMINED IN RELATION TO CORRESPONDING GENE EXPRESSION FOR FUNCTIONAL EVIDENCE OF GENE REGULATION. RESULTS: IN ADJUSTED ANALYSES, WE OBSERVED FOUR DIFFERENTIALLY METHYLATED CPG SITES WITH URINARY TOTAL ARSENIC CONCENTRATION AND THREE DIFFERENTIALLY METHYLATED CPG SITES WITH BLOOD ARSENIC CONCENTRATION, BASED ON THE BONFERRONI-CORRECTED SIGNIFICANCE THRESHOLD OF P < 1 X 10(-7). METHYLATION OF PLA2G2C (PROBE CG04605617) WAS THE MOST SIGNIFICANTLY ASSOCIATED LOCUS IN RELATION TO BOTH URINARY (P = 3.40 X 10(-11)) AND BLOOD ARSENIC CONCENTRATIONS (P = 1.48 X 10(-11)). THREE ADDITIONAL NOVEL METHYLATION LOCI-SQSTM1 (CG01225779), SLC4A4 (CG06121226), AND IGH (CG13651690)--WERE ALSO SIGNIFICANTLY ASSOCIATED WITH ARSENIC EXPOSURE. FURTHER, THERE WAS EVIDENCE OF METHYLATION-RELATED GENE REGULATION BASED ON GENE EXPRESSION FOR A SUBSET OF DIFFERENTIALLY METHYLATED LOCI. CONCLUSIONS: WE OBSERVED SIGNIFICANT ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND GENE-SPECIFIC DIFFERENTIAL WHITE BLOOD CELL DNA METHYLATION, SUGGESTING THAT EPIGENETIC MODIFICATIONS MAY BE AN IMPORTANT PATHWAY UNDERLYING ARSENIC TOXICITY. THE SPECIFIC DIFFERENTIALLY METHYLATED LOCI IDENTIFIED MAY INFORM POTENTIAL PATHWAYS FOR FUTURE INTERVENTIONS. 2015 3 382 56 AN EPIGENOME-WIDE STUDY OF BODY MASS INDEX AND DNA METHYLATION IN BLOOD USING PARTICIPANTS FROM THE SISTER STUDY COHORT. BACKGROUND/OBJECTIVES: THE RELATIONSHIP BETWEEN OBESITY AND CHRONIC DISEASE RISK IS WELL-ESTABLISHED; THE UNDERLYING BIOLOGICAL MECHANISMS DRIVING THIS RISK INCREASE MAY INCLUDE OBESITY-RELATED EPIGENETIC MODIFICATIONS. TO EXPLORE THIS HYPOTHESIS, WE CONDUCTED A GENOME-WIDE ANALYSIS OF DNA METHYLATION AND BODY MASS INDEX (BMI) USING DATA FROM A SUBSET OF WOMEN IN THE SISTER STUDY. SUBJECTS/METHODS: THE SISTER STUDY IS A COHORT OF 50 884 US WOMEN WHO HAD A SISTER WITH BREAST CANCER BUT WERE FREE OF BREAST CANCER THEMSELVES AT ENROLLMENT. STUDY PARTICIPANTS COMPLETED EXAMINATIONS WHICH INCLUDED MEASUREMENTS OF HEIGHT AND WEIGHT, AND PROVIDED BLOOD SAMPLES. BLOOD DNA METHYLATION DATA GENERATED WITH THE ILLUMINA INFINIUM HUMANMETHYLATION27 BEADCHIP ARRAY COVERING 27,589 CPG SITES WAS AVAILABLE FOR 871 WOMEN FROM A PRIOR STUDY OF BREAST CANCER AND DNA METHYLATION. TO IDENTIFY DIFFERENTIALLY METHYLATED CPG SITES ASSOCIATED WITH BMI, WE ANALYZED THIS METHYLATION DATA USING ROBUST LINEAR REGRESSION WITH ADJUSTMENT FOR AGE AND CASE STATUS. FOR THOSE CPGS PASSING THE FALSE DISCOVERY RATE SIGNIFICANCE LEVEL, WE EXAMINED THE ASSOCIATION IN A REPLICATION SET COMPRISED OF A NON-OVERLAPPING GROUP OF 187 WOMEN FROM THE SISTER STUDY WHO HAD DNA METHYLATION DATA GENERATED USING THE INFINIUM HUMANMETHYLATION450 BEADCHIP ARRAY. ANALYSIS OF THIS EXPANDED 450 K ARRAY IDENTIFIED ADDITIONAL BMI-ASSOCIATED SITES WHICH WERE INVESTIGATED WITH TARGETED PYROSEQUENCING. RESULTS: FOUR CPG SITES REACHED GENOME-WIDE SIGNIFICANCE (FALSE DISCOVERY RATE (FDR) Q<0.05) IN THE DISCOVERY SET AND ASSOCIATIONS FOR ALL FOUR WERE SIGNIFICANT AT STRICT BONFERRONI CORRECTION IN THE REPLICATION SET. AN ADDITIONAL 23 SITES PASSED FDR IN THE REPLICATION SET AND FIVE WERE REPLICATED BY PYROSEQUENCING IN THE DISCOVERY SET. SEVERAL OF THE GENES IDENTIFIED INCLUDING ANGPT4, RORC, SOCS3, FSD2, XYLT1, ABCG1, STK39, ASB2 AND CRHR2 HAVE BEEN LINKED TO OBESITY AND OBESITY-RELATED CHRONIC DISEASES. CONCLUSIONS: OUR FINDINGS SUPPORT THE HYPOTHESIS THAT OBESITY-RELATED EPIGENETIC DIFFERENCES ARE DETECTABLE IN BLOOD AND MAY BE RELATED TO RISK OF CHRONIC DISEASE. 2017 4 6080 47 THE EFFECT OF DNA METHYLATION IN THE DEVELOPMENT AND PROGRESSION OF CHRONIC KIDNEY DISEASE IN THE GENERAL POPULATION: AN EPIGENOME-WIDE ASSOCIATION STUDY USING THE KOREAN GENOME AND EPIDEMIOLOGY STUDY DATABASE. BACKGROUND: ALTHOUGH KNOWLEDGE OF THE GENETIC FACTORS INFLUENCING KIDNEY DISEASE IS INCREASING, EPIGENETIC PROFILES, WHICH ARE ASSOCIATED WITH CHRONIC KIDNEY DISEASE (CKD), HAVE NOT BEEN FULLY ELUCIDATED. WE SOUGHT TO IDENTIFY THE DNA METHYLATION STATUS OF CPG SITES ASSOCIATED WITH REDUCED KIDNEY FUNCTION AND EXAMINE WHETHER THE IDENTIFIED CPG SITES ARE ASSOCIATED WITH CKD DEVELOPMENT. METHOD: WE ANALYZED DNA METHYLATION PATTERNS OF 440 PARTICIPANTS IN THE KOREAN GENOME AND EPIDEMIOLOGY STUDY (KOGES) WITH ESTIMATED GLOMERULAR FILTRATION RATES (EGFRS) >/= 60 ML/MIN/1.73 M(2) AT BASELINE. CKD DEVELOPMENT WAS DEFINED AS A DECREASE IN THE EGFR OF <60 AT ANY TIME DURING AN 8-YEAR FOLLOW-UP PERIOD ("CKD PREDICTION" ANALYSIS). IN ADDITION, AMONG THE 440 PARTICIPANTS, 49 PARTICIPANTS WHO UNDERWENT A SECOND METHYLATION PROFILING WERE ASSESSED FOR AN ASSOCIATION BETWEEN A DECLINE IN KIDNEY FUNCTION AND CHANGES IN THE DEGREE OF METHYLATION OF CPG SITES DURING THE 8 YEARS ("KIDNEY FUNCTION SLOPE" ANALYSIS). RESULTS: IN THE CKD PREDICTION ANALYSIS, METHYLATION PROFILES OF A TOTAL OF 403,129 CPG SITES WERE EVALUATED AT BASELINE IN 440 PARTICIPANTS, AND INCREASED AND DECREASED METHYLATION OF 268 AND 189 CPG SITES, RESPECTIVELY, WERE SIGNIFICANTLY CORRELATED WITH THE DEVELOPMENT OF CKD IN MULTIVARIABLE LOGISTIC REGRESSION. DURING KIDNEY FUNCTION SLOPE ANALYSIS USING FOLLOW-UP METHYLATION PROFILES OF 49 PARTICIPANTS, THE PERCENT METHYLATION CHANGES IN 913 CPG SITES SHOWED A LINEAR RELATIONSHIP WITH THE PERCENT CHANGE IN EGFR DURING 8 YEARS. DURING FUNCTIONAL ENRICHMENT ANALYSES FOR SIGNIFICANT CPG SITES FOUND IN THE CKD PREDICTION AND KIDNEY FUNCTION SLOPE ANALYSES, WE FOUND THAT THOSE CPG SITES REPRESENTED MAPK, PI3K/AKT, AND RAP1 PATHWAYS. IN ADDITION, THREE CPG SITES FROM THREE GENES, NPHS2, CHCHD4, AND AHR, WERE FOUND TO BE SIGNIFICANT IN THE CKD PREDICTION ANALYSIS AND RELATED TO A DECLINE IN KIDNEY FUNCTION. CONCLUSION: IT IS SUGGESTED THAT DNA METHYLATION ON SPECIFIC GENES IS ASSOCIATED WITH THE DEVELOPMENT OF CKD AND THE DETERIORATION OF KIDNEY FUNCTION. 2023 5 6190 47 THE IMPACT OF METHYLATION QUANTITATIVE TRAIT LOCI (MQTLS) ON ACTIVE SMOKING-RELATED DNA METHYLATION CHANGES. BACKGROUND: METHYLATION QUANTITATIVE TRAIT LOCI (MQTLS) ARE THE GENETIC VARIANTS THAT MAY AFFECT THE DNA METHYLATION PATTERNS OF CPG SITES. HOWEVER, THEIR ROLES IN INFLUENCING THE DISTURBANCES OF SMOKING-RELATED EPIGENETIC CHANGES HAVE NOT BEEN WELL ESTABLISHED. THIS STUDY WAS CONDUCTED TO ADDRESS WHETHER MQTLS EXIST IN THE VICINITY OF SMOKING-RELATED CPG SITES (+/- 50 KB) AND TO EXAMINE THEIR ASSOCIATIONS WITH SMOKING EXPOSURE AND ALL-CAUSE MORTALITY IN OLDER ADULTS. RESULTS: WE OBTAINED DNA METHYLATION PROFILES IN WHOLE BLOOD SAMPLES BY ILLUMINA INFINIUM HUMAN METHYLATION 450 BEADCHIP ARRAY OF TWO INDEPENDENT SUBSAMPLES OF THE ESTHER STUDY (DISCOVERY SET, N = 581; VALIDATION SET, N = 368) AND THEIR CORRESPONDING GENOTYPING DATA USING THE ILLUMINA INFINIUM ONCOARRAY BEADCHIP. AFTER CORRECTION FOR MULTIPLE TESTING (FDR), WE SUCCESSFULLY IDENTIFIED THAT 70 OUT OF 151 PREVIOUSLY REPORTED SMOKING-RELATED CPG SITES WERE SIGNIFICANTLY ASSOCIATED WITH 192 SNPS WITHIN THE 50 KB SEARCH WINDOW OF EACH LOCUS. THE 192 MQTLS SIGNIFICANTLY INFLUENCED THE ACTIVE SMOKING-RELATED DNA METHYLATION CHANGES, WITH PERCENTAGE CHANGES RANGING FROM 0.01 TO 18.96%, ESPECIALLY FOR THE WEAKLY/MODERATELY SMOKING-RELATED CPG SITES. HOWEVER, THESE IDENTIFIED MQTLS WERE NOT DIRECTLY ASSOCIATED WITH ACTIVE SMOKING EXPOSURE OR ALL-CAUSE MORTALITY. CONCLUSIONS: OUR FINDINGS CLEARLY DEMONSTRATED THAT IF NOT DEALT WITH PROPERLY, THE MQTLS MIGHT IMPAIR THE POWER OF EPIGENETIC-BASED MODELS OF SMOKING EXPOSURE TO A CERTAIN EXTENT. IN ADDITION, SUCH GENETIC VARIANTS COULD BE THE KEY FACTOR TO DISTINGUISH BETWEEN THE HERITABLE AND SMOKING-INDUCED IMPACT ON EPIGENOME DISPARITIES. THESE MQTLS ARE OF SPECIAL IMPORTANCE WHEN DNA METHYLATION MARKERS MEASURED BY ILLUMINA INFINIUM ASSAY ARE USED FOR ANY COMPARATIVE POPULATION STUDIES RELATED TO SMOKING-RELATED CANCERS AND CHRONIC DISEASES. 2017 6 2079 42 EPIGENETIC DNA METHYLATION CHANGES ASSOCIATED WITH HEADACHE CHRONIFICATION: A RETROSPECTIVE CASE-CONTROL STUDY. BACKGROUND THE BIOLOGICAL MECHANISMS OF HEADACHE CHRONIFICATION ARE POORLY UNDERSTOOD. WE AIMED TO IDENTIFY CHANGES IN DNA METHYLATION ASSOCIATED WITH THE TRANSFORMATION FROM EPISODIC TO CHRONIC HEADACHE. METHODS PARTICIPANTS WERE RECRUITED FROM THE POPULATION-BASED NORWEGIAN HUNT STUDY. THIRTY-SIX FEMALE HEADACHE PATIENTS WHO TRANSFORMED FROM EPISODIC TO CHRONIC HEADACHE BETWEEN BASELINE AND FOLLOW-UP 11 YEARS LATER WERE MATCHED AGAINST 35 CONTROLS WITH EPISODIC HEADACHE. DNA METHYLATION WAS QUANTIFIED AT 485,000 CPG SITES, AND CHANGES IN METHYLATION LEVEL AT THESE SITES WERE COMPARED BETWEEN CASES AND CONTROLS BY LINEAR REGRESSION ANALYSIS. DATA WERE ANALYZED IN TWO STAGES (STAGES 1 AND 2) AND IN A COMBINED META-ANALYSIS. RESULTS NONE OF THE TOP 20 CPG SITES IDENTIFIED IN STAGE 1 REPLICATED IN STAGE 2 AFTER MULTIPLE TESTING CORRECTION. IN THE COMBINED META-ANALYSIS THE STRONGEST ASSOCIATED CPG SITES WERE RELATED TO SH2D5 AND NPTX2, TWO BRAIN-EXPRESSED GENES INVOLVED IN THE REGULATION OF SYNAPTIC PLASTICITY. FUNCTIONAL ENRICHMENT ANALYSIS POINTED TO PROCESSES INCLUDING CALCIUM ION BINDING AND ESTROGEN RECEPTOR PATHWAYS. CONCLUSION IN THIS FIRST GENOME-WIDE STUDY OF DNA METHYLATION IN HEADACHE CHRONIFICATION SEVERAL POTENTIALLY IMPLICATED LOCI AND PROCESSES WERE IDENTIFIED. THE STUDY EXEMPLIFIES THE USE OF PROSPECTIVELY COLLECTED POPULATION COHORTS TO SEARCH FOR EPIGENETIC MECHANISMS OF DISEASE. 2018 7 490 46 ASSESSING THE IMPACT OF ARSENIC METABOLISM EFFICIENCY ON DNA METHYLATION USING MENDELIAN RANDOMIZATION. BACKGROUND: ARSENIC EXPOSURE AFFECTS >100 MILLION PEOPLE GLOBALLY AND INCREASES RISK FOR CHRONIC DISEASES. ONE POSSIBLE TOXICITY MECHANISM IS EPIGENETIC MODIFICATION. PREVIOUS EPIGENOME-WIDE ASSOCIATION STUDIES (EWAS) HAVE IDENTIFIED ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND CPG-SPECIFIC DNA METHYLATION. TO PROVIDE ADDITIONAL EVIDENCE THAT OBSERVED ASSOCIATIONS REPRESENT CAUSAL RELATIONSHIPS, WE EXAMINE THE ASSOCIATION BETWEEN GENETIC DETERMINANTS OF ARSENIC METABOLISM EFFICIENCY (PERCENT DIMETHYLARSINIC ACID, DMA%, IN URINE) AND DNA METHYLATION AMONG INDIVIDUALS FROM THE HEALTH EFFECTS OF ARSENIC LONGITUDINAL STUDY (N = 379) AND BANGLADESH VITAMIN E AND SELENIUM TRIAL (N = 393). METHODS: WE USED MULTIVARIATE LINEAR MODELS TO ASSESS THE ASSOCIATION OF METHYLATION AT 221 ARSENIC-ASSOCIATED CPGS WITH DMA% AND MEASURES OF GENETICALLY PREDICTED DMA% DERIVED FROM THREE SNPS (RS9527, RS11191527, AND RS61735836). WE ALSO CONDUCTED TWO-SAMPLE MENDELIAN RANDOMIZATION ANALYSES TO ESTIMATE THE ASSOCIATION BETWEEN ARSENIC METABOLISM EFFICIENCY AND CPG METHYLATION. RESULTS: AMONG THE ASSOCIATIONS BETWEEN DMA% AND METHYLATION AT EACH OF 221 CPGS, 64% WERE DIRECTIONALLY CONSISTENT WITH ASSOCIATIONS OBSERVED BETWEEN ARSENIC EXPOSURE AND THE 221 CPGS FROM A PRIOR EWAS. SIMILARLY, AMONG THE ASSOCIATIONS BETWEEN GENETICALLY PREDICTED DMA% AND EACH CPG, 62% WERE DIRECTIONALLY CONSISTENT WITH THE PRIOR EWAS RESULTS. TWO-SAMPLE MENDELIAN RANDOMIZATION ANALYSES PRODUCED SIMILAR CONCLUSIONS. CONCLUSION: OUR FINDINGS SUPPORT THE HYPOTHESIS THAT ARSENIC EXPOSURE EFFECTS DNA METHYLATION AT SPECIFIC CPGS IN WHOLE BLOOD. OUR NOVEL APPROACH FOR ASSESSING THE IMPACT OF ARSENIC EXPOSURE ON DNA METHYLATION REQUIRES LARGER SAMPLES IN ORDER TO DRAW MORE ROBUST CONCLUSIONS FOR SPECIFIC CPG SITES. 2020 8 2627 47 EPIGENOME-WIDE ASSOCIATION STUDY OF ADIPOSITY AND FUTURE RISK OF OBESITY-RELATED DISEASES. BACKGROUND: OBESITY IS AN ESTABLISHED RISK FACTOR FOR SEVERAL COMMON CHRONIC DISEASES SUCH AS BREAST AND COLORECTAL CANCER, METABOLIC AND CARDIOVASCULAR DISEASES; HOWEVER, THE BIOLOGICAL BASIS FOR THESE RELATIONSHIPS IS NOT FULLY UNDERSTOOD. TO EXPLORE THE ASSOCIATION OF OBESITY WITH THESE CONDITIONS, WE INVESTIGATED PERIPHERAL BLOOD LEUCOCYTE (PBL) DNA METHYLATION MARKERS FOR ADIPOSITY AND THEIR CONTRIBUTION TO RISK OF INCIDENT BREAST AND COLORECTAL CANCER AND MYOCARDIAL INFARCTION. METHODS: DNA METHYLATION PROFILES (ILLUMINA INFINIUM((R)) HUMANMETHYLATION450 BEADCHIP) FROM 1941 INDIVIDUALS FROM FOUR POPULATION-BASED EUROPEAN COHORTS WERE ANALYSED IN RELATION TO BODY MASS INDEX, WAIST CIRCUMFERENCE, WAIST-HIP AND WAIST-HEIGHT RATIO WITHIN A META-ANALYTICAL FRAMEWORK. IN A SUBSET OF THESE INDIVIDUALS, DATA ON GENOME-WIDE GENE EXPRESSION LEVEL, BIOMARKERS OF GLUCOSE AND LIPID METABOLISM WERE ALSO AVAILABLE. VALIDATION OF METHYLATION MARKERS ASSOCIATED WITH ALL ADIPOSITY MEASURES WAS PERFORMED IN 358 INDIVIDUALS. FINALLY, WE INVESTIGATED THE ASSOCIATION OF OBESITY-RELATED METHYLATION MARKS WITH BREAST, COLORECTAL CANCER AND MYOCARDIAL INFARCTION WITHIN RELEVANT SUBSETS OF THE DISCOVERY POPULATION. RESULTS: WE IDENTIFIED 40 CPG LOCI WITH METHYLATION LEVELS ASSOCIATED WITH AT LEAST ONE ADIPOSITY MEASURE. OF THESE, ONE CPG LOCUS (CG06500161) IN ABCG1 WAS ASSOCIATED WITH ALL FOUR ADIPOSITY MEASURES (P = 9.07X10(-)(8) TO 3.27X10(-18)) AND LOWER TRANSCRIPTIONAL ACTIVITY OF THE FULL-LENGTH ISOFORM OF ABCG1 (P = 6.00X10(-7)), HIGHER TRIGLYCERIDE LEVELS (P = 5.37X10(-)(9)) AND HIGHER TRIGLYCERIDES-TO-HDL CHOLESTEROL RATIO (P = 1.03X10(-10)). OF THE 40 INFORMATIVE AND OBESITY-RELATED CPG LOCI, TWO (IN IL2RB AND FGF18) WERE SIGNIFICANTLY ASSOCIATED WITH COLORECTAL CANCER (INVERSELY, P < 1.6X10(-3)) AND ONE INTERGENIC LOCUS ON CHROMOSOME 1 WAS INVERSELY ASSOCIATED WITH MYOCARDIAL INFARCTION (P < 1.25X10(-3)), INDEPENDENTLY OF OBESITY AND ESTABLISHED RISK FACTORS. CONCLUSION: OUR RESULTS SUGGEST THAT EPIGENETIC CHANGES, IN PARTICULAR ALTERED DNA METHYLATION PATTERNS, MAY BE AN INTERMEDIATE BIOMARKER AT THE INTERSECTION OF OBESITY AND OBESITY-RELATED DISEASES, AND COULD OFFER CLUES AS TO UNDERLYING BIOLOGICAL MECHANISMS. 2018 9 2488 44 EPIGENETICALLY DYSREGULATED GENES AND PATHWAYS IMPLICATED IN THE PATHOGENESIS OF NON-SYNDROMIC HIGH MYOPIA. MYOPIA, COMMONLY REFERRED TO AS NEARSIGHTEDNESS, IS ONE OF THE MOST COMMON CAUSES OF VISUAL DISABILITY THROUGHOUT THE WORLD. IT AFFECTS MORE PEOPLE WORLDWIDE THAN ANY OTHER CHRONIC VISUAL IMPAIRMENT CONDITION. ALTHOUGH THE PREVALENCE VARIES AMONG VARIOUS ETHNIC GROUPS, THE INCIDENCE OF MYOPIA IS INCREASING IN ALL POPULATIONS ACROSS GLOBE. THUS, IT IS CONSIDERED A PRESSING PUBLIC HEALTH PROBLEM. BOTH GENETICS AND ENVIRONMENT PLAY A ROLE IN DEVELOPMENT OF MYOPIA. TO ELUCIDATE THE EPIGENETIC MECHANISM(S) UNDERLYING THE PATHOPHYSIOLOGY OF HIGH-MYOPIA, WE CONDUCTED METHYLATION PROFILING IN 18 CASES AND 18 MATCHED CONTROLS (AGED 4-12 YEARS), USING ILLUMINA METHYLATIONEPIC BEADCHIPS ARRAY. THE DEGREE OF MYOPIA WAS VARIABLE AMONG SUBJECTS, RANGING FROM -6 TO -15D. WE IDENTIFIED 1541 HYPERMETHYLATED CPGS, REPRESENTING 1745 GENES (2.0-FOLD OR HIGHER) (FALSE DISCOVERY RATE (FDR) P /= 0.75 IN HIGH-MYOPIA SUBJECTS COMPARED TO CONTROLS. AMONG THESE, 48 CPGS HAD EXCELLENT CORRELATION (AUC >/= 0.90). HEREIN, WE PRESENT THE FIRST GENOME-WIDE DNA METHYLATION ANALYSIS IN A UNIQUE HIGH-MYOPIA COHORT, SHOWING EXTENSIVE AND DISCRETE METHYLATION CHANGES RELATIVE TO CONTROLS. THE GENES WE IDENTIFIED HOLD SIGNIFICANT POTENTIAL AS TARGETS FOR NOVEL THERAPEUTIC INTERVENTION EITHER ALONE, OR IN COMBINATION. 2019 10 1573 47 DNA METHYLATION PATTERNS IN NEWBORNS EXPOSED TO TOBACCO IN UTERO. BACKGROUND: MATERNAL SMOKING DURING PREGNANCY IS A MAJOR RISK FACTOR FOR ADVERSE HEALTH OUTCOMES. THE MAIN OBJECTIVE OF THE STUDY WAS TO ASSESS THE IMPACT OF IN UTERO TOBACCO EXPOSURE ON DNA METHYLATION IN CHILDREN BORN AT TERM WITH APPROPRIATE WEIGHT AT BIRTH. METHODS: TWENTY MOTHER-NEWBORN DYADS, AFTER UNCOMPLICATED PREGNANCIES, IN THE ABSENCE OF PERINATAL ILLNESS WERE INCLUDED. ALL MOTHERS WERE HEALTHY WITH NO CARDIOVASCULAR RISK FACTORS, EXCEPT FOR THE ASSOCIATED RISKS AMONG THOSE MOTHERS WHO SMOKED. UMBILICAL CORD BLOOD AND MATERNAL PERIPHERAL VENOUS BLOOD WERE COLLECTED AND AN EPIGENOME-WIDE ASSOCIATION STUDY WAS PERFORMED USING A 450 K EPIGENOME-WIDE SCAN (ILLUMINA INFINIUM HUMANMETHYLATION 450BEADCHIP) WITH ADJUSTMENT TO NORMALIZE THE DNA METHYLATION FOR DATA CELL VARIABILITY IN WHOLE BLOOD. RESULTS: THE MATERNAL PLASMATIC COTININE LEVELS RANGED FROM 10.70-115.40 NG/ML IN THE EXPOSED GROUP TO 0-0.59 NG/ML IN THE NON-EXPOSED GROUP. AFTER ADJUSTING FOR MULTIPLE COMPARISONS IN 427102 PROBES, STATISTICALLY SIGNIFICANT DIFFERENCES FOR 31 CPG SITES, ASSOCIATED TO 25 GENES WERE OBSERVED. THERE WAS A GREATER THAN EXPECTED PROPORTION OF STATISTICALLY-SIGNIFICANT LOCI LOCATED IN CPG ISLANDS (FISHER'S EXACT TEST, P = 0.029) AND OF THOSE CPG ISLANDS, 90.3% EXHIBIT HIGHER METHYLATION LEVELS IN THE EXPOSED GROUP. THE MOST STRIKING AND SIGNIFICANT CPG SITE, CG05727225, IS LOCATED IN THE CHROMOSOME 11P15.4, WITHIN THE ADRENOMEDULLIN GENE. CONCLUSIONS: IN UTERO TOBACCO EXPOSURE, EVEN IN THE ABSENCE OF FETAL GROWTH RESTRICTION, MAY ALTER THE EPIGENOME, CONTRIBUTING TO GLOBAL DNA HYPOMETHYLATION. THEREFORE, DNA STATUS CAN BE USED AS A BIOMARKER OF PRENATAL INSULTS. CONSIDERING THE POSSIBILITY TO REVERSE EPIGENETIC MODIFICATIONS, A WINDOW OF OPPORTUNITY EXISTS TO CHANGE THE PROGRAMMED CHRONIC DISEASE. 2015 11 1537 37 DNA METHYLATION IN ADOLESCENTS WITH ANXIETY DISORDER: A LONGITUDINAL STUDY. ANXIETY DISORDERS (AD) TYPICALLY MANIFEST IN CHILDREN AND ADOLESCENTS AND MIGHT PERSIST INTO ADULTHOOD. HOWEVER, THERE ARE STILL FEW DATA CONCERNING EPIGENETIC MECHANISMS ASSOCIATED WITH ONSET, PERSISTENCE OR REMISSION OF AD OVER TIME. WE INVESTIGATED A COHORT OF ADOLESCENTS AND YOUNG ADULTS AT BASELINE (AGE; 13.19 +/- 2.38) AND AFTER 5 YEARS AND CLASSIFIED THEM ACCORDING TO THE AD DIAGNOSIS AND THEIR LONGITUDINAL TRAJECTORIES INTO 4 GROUPS: (1) TYPICALLY DEVELOPING COMPARISONS (TDC; CONTROL GROUP, N = 14); (2) INCIDENT (AD IN THE SECOND EVALUATION ONLY, N = 11); (3) PERSISTENT (AD IN BOTH EVALUATIONS, N = 14) AND (4) REMITTENT (AD IN THE FIRST EVALUATION ONLY, N = 8). DNA METHYLATION WAS EVALUATED WITH THE INFINIUM HUMANMETHYLATION450 BEADCHIP FROM SALIVA SAMPLES COLLECTED AT BOTH EVALUATIONS. GENE SET ENRICHMENT ANALYSIS WAS APPLIED TO CONSIDER BIOLOGICAL PATHWAYS. WE FOUND DECREASED DNA METHYLATION IN TDC GROUP WHILE THE CHRONIC CASES OF AD PRESENTED HYPERMETHYLATION IN CENTRAL NERVOUS SYSTEM DEVELOPMENT PATHWAYS. MOREOVER, WE SHOWED THAT THIS PERSISTENT GROUP ALSO PRESENTED HYPERMETHYLATION WHILE THE OTHER THREE GROUPS WERE ASSOCIATED WITH HYPOMETHYLATION IN NERVOUS SYSTEM DEVELOPMENT PATHWAY. INCIDENCE AND REMISSION GROUPS WERE ASSOCIATED WITH INCREASED AND DECREASED METHYLATION IN NEURON DEVELOPMENT PATHWAYS, RESPECTIVELY. LARGER STUDIES ARE LIKELY TO DETECT SPECIFIC GENES RELEVANT TO AD. 2018 12 6083 44 THE EFFECT OF SMOKING ON DNA METHYLATION OF PERIPHERAL BLOOD MONONUCLEAR CELLS FROM AFRICAN AMERICAN WOMEN. BACKGROUND: REGULAR SMOKING IS ASSOCIATED WITH A WIDE VARIETY OF SYNDROMES WITH PROMINENT INFLAMMATORY COMPONENTS SUCH AS CANCER, OBESITY AND TYPE 2 DIABETES. HEAVY REGULAR SMOKING IS ALSO ASSOCIATED WITH CHANGES IN THE DNA METHYLATION OF PERIPHERAL MONONUCLEAR CELLS. HOWEVER, IN YOUNGER SMOKERS, INFLAMMATORY EPIGENETIC FINDINGS ARE LARGELY ABSENT WHICH SUGGESTS THE INFLAMMATORY RESPONSE(S) TO SMOKING MAY BE DOSE DEPENDENT. TO HELP UNDERSTAND WHETHER PERIPHERAL MONONUCLEAR CELLS HAVE A ROLE IN MEDIATING THESE RESPONSES IN OLDER SMOKERS WITH HIGHER CUMULATIVE SMOKE EXPOSURE, WE EXAMINED GENOME-WIDE DNA METHYLATION IN A GROUP OF WELL CHARACTERIZED ADULT AFRICAN AMERICAN SUBJECTS INFORMATIVE FOR SMOKING, AS WELL AS SERUM C-REACTIVE PROTEIN (CRP) AND INTERLEUKIN-6 RECEPTOR (IL6R) LEVELS. IN ADDITION, COMPLEMENTARY BIOINFORMATIC ANALYSES WERE CONDUCTED TO DELINEATE POSSIBLE PATHWAYS AFFECTED BY LONG-TERM SMOKING. RESULTS: GENOME-WIDE DNA METHYLATION ANALYSIS WITH RESPECT TO SMOKING STATUS YIELDED 910 SIGNIFICANT LOCI AFTER BENJAMINI-HOCHBERG CORRECTION. IN PARTICULAR, TWO LOCI FROM THE AHRR GENE (CG05575921 AND CG23576855) AND ONE LOCUS FROM THE GPR15 GENE (CG19859270) WERE IDENTIFIED AS HIGHLY SIGNIFICANTLY DIFFERENTIALLY METHYLATED BETWEEN SMOKERS AND NON-SMOKERS. THE BIOINFORMATIC ANALYSES SHOWED THAT LONG-TERM CHRONIC SMOKING IS ASSOCIATED WITH ALTERED PROMOTER DNA METHYLATION OF GENES CODING FOR PROTEINS MAPPING TO CRITICAL SUB-NETWORKS MODERATING INFLAMMATION, IMMUNE FUNCTION, AND COAGULATION. CONCLUSIONS: WE CONCLUDE THAT CHRONIC REGULAR SMOKING IS ASSOCIATED WITH CHANGES IN PERIPHERAL MONONUCLEAR CELL METHYLATION SIGNATURE WHICH PERTURB INFLAMMATORY AND IMMUNE FUNCTION PATHWAYS AND MAY CONTRIBUTE TO INCREASED VULNERABILITY FOR COMPLEX ILLNESSES WITH INFLAMMATORY COMPONENTS. 2014 13 1909 43 ENRICHMENT OF GENOMIC PATHWAYS BASED ON DIFFERENTIAL DNA METHYLATION PROFILES ASSOCIATED WITH CHRONIC MUSCULOSKELETAL PAIN IN OLDER ADULTS: AN EXPLORATORY STUDY. OUR STUDY AIMED TO IDENTIFY DIFFERENTIALLY METHYLATED CPGS/REGIONS AND THEIR ENRICHED GENOMIC PATHWAYS ASSOCIATED WITH UNDERLYING CHRONIC MUSCULOSKELETAL PAIN IN OLDER INDIVIDUALS. WE RECRUITED COGNITIVELY HEALTHY OLDER ADULTS WITH (N = 20) AND WITHOUT (N = 9) SELF-REPORTED MUSCULOSKELETAL PAIN AND COLLECTED DNA FROM PERIPHERAL BLOOD THAT WAS ANALYZED USING METHYLATIONEPIC ARRAYS. WE IDENTIFIED 31,739 HYPERMETHYLATED CPG AND 10,811 HYPOMETHYLATED CPG PROBES (PS 0.05). NON-HISPANIC BLACK INDIVIDUALS WERE OVERREPRESENTED IN THE PAIN GROUP (P = 0.003). AT RAW P < 0.05 CUTOFF, WE IDENTIFIED A TOTAL OF 19,710 CPG PROBES, INCLUDING 13,951 HYPERMETHYLATED CPG PROBES, FOR WHICH DNA METHYLATION LEVEL WAS HIGHER IN THE GROUPS WITH HIGHEST PAIN GRADES. WE ALSO IDENTIFIED 5,759 HYPOMETHYLATED CPG PROBES FOR WHICH DNA METHYLATION LEVEL WAS LOWER IN THE PAIN GROUPS WITH HIGHER PAIN GRADES. IPA REVEALED THAT PAIN-RELATED DMRS WERE ENRICHED ACROSS MULTIPLE PATHWAYS AND UPSTREAM REGULATORS. THE TOP 10 CANONICAL PATHWAYS WERE LINKED TO CELLULAR SIGNALING PROCESSES RELATED TO IMMUNE RESPONSES (I.E., ANTIGEN PRESENTATION, PD-1, PD-L1 CANCER IMMUNOTHERAPY, B CELL DEVELOPMENT, IL-4 SIGNALING, TH1 AND TH2 ACTIVATION PATHWAY, AND PHAGOSOME MATURATION). MOREOVER, IN TERMS OF UPSTREAM REGULATORS, NDUFAF3 WAS THE MOST SIGNIFICANT (P = 8.6E-04) UPSTREAM REGULATOR. OUR FINDINGS SUPPORT PREVIOUS PRELIMINARY WORK SUGGESTING THE IMPORTANCE OF EPIGENETIC REGULATION OF THE IMMUNE SYSTEM IN KNEE PAIN AND THE NEED FOR FUTURE WORK TO UNDERSTAND THE EPIGENETIC CONTRIBUTIONS TO CHRONIC PAIN. 2022 18 6311 35 THE RELATION BETWEEN DNA METHYLATION PATTERNS AND SERUM CYTOKINE LEVELS IN COMMUNITY-DWELLING ADULTS: A PRELIMINARY STUDY. BACKGROUND: THE LEVELS OF CIRCULATING CYTOKINES FLUCTUATE WITH AGE, ACUTE ILLNESS, AND CHRONIC DISEASE, AND ARE PREDICTIVE OF MORTALITY; THIS IS ALSO TRUE FOR PATTERNS OF DNA (CPG) METHYLATION. GIVEN THAT IMMUNE CELLS ARE PARTICULARLY SENSITIVE TO CHANGES IN THE CONCENTRATION OF CYTOKINES IN THEIR MICROENVIRONMENT, WE HYPOTHESIZED THAT SERUM LEVELS OF TNF, IL-6, IL-8 AND IL-10 WOULD CORRELATE WITH GENOME-WIDE ALTERATIONS IN THE DNA METHYLATION LEVELS OF BLOOD LEUKOCYTES. TO TEST THIS, WE EVALUATED COMMUNITY-DWELLING ADULTS (N = 14; 48-78 YEARS OLD) RECRUITED TO A PILOT STUDY FOR THE CANADIAN LONGITUDINAL STUDY ON AGING (CLSA), EXAMINING DNA METHYLATION PATTERNS IN PERIPHERAL BLOOD MONONUCLEAR CELLS USING THE ILLUMINA HUMANMETHYLATION 450 K BEADCHIP. RESULTS: WE SHOW THAT, APART FROM AGE, SERUM IL-10 LEVELS EXHIBITED THE MOST SUBSTANTIAL ASSOCIATION TO DNA METHYLATION PATTERNS, FOLLOWED BY TNF, IL-6 AND IL-8. FURTHERMORE, WHILE THE LEVELS OF THESE CYTOKINES WERE HIGHER IN ELDERLY ADULTS, NO ASSOCIATIONS WITH EPIGENETIC ACCELERATED AGING, DERIVED USING THE EPIGENETIC CLOCK, WERE OBSERVED. CONCLUSIONS: AS A PRELIMINARY STUDY WITH A SMALL SAMPLE SIZE, THE CONCLUSIONS DRAWN FROM THIS WORK MUST BE VIEWED WITH CAUTION; HOWEVER, OUR OBSERVATIONS ARE ENCOURAGING AND CERTAINLY WARRANT MORE SUITABLY POWERED STUDIES OF THIS RELATIONSHIP. 2017 19 3063 62 GENOME-WIDE DNA METHYLATION AND LONG-TERM AMBIENT AIR POLLUTION EXPOSURE IN KOREAN ADULTS. BACKGROUND: AMBIENT AIR POLLUTION IS ASSOCIATED WITH NUMEROUS ADVERSE HEALTH OUTCOMES, BUT THE UNDERLYING MECHANISMS ARE NOT WELL UNDERSTOOD; EPIGENETIC EFFECTS INCLUDING ALTERED DNA METHYLATION COULD PLAY A ROLE. TO EVALUATE ASSOCIATIONS OF LONG-TERM AIR POLLUTION EXPOSURE WITH DNA METHYLATION IN BLOOD, WE CONDUCTED AN EPIGENOME-WIDE ASSOCIATION STUDY IN A KOREAN CHRONIC OBSTRUCTIVE PULMONARY DISEASE COHORT (N = 100 INCLUDING 60 CASES) USING ILLUMINA'S INFINIUM HUMANMETHYLATION450K BEADCHIP. ANNUAL AVERAGE CONCENTRATIONS OF PARTICULATE MATTER 20 INDIVIDUALS IN EACH COMPARISON GROUP, AND EXAMINED ONE OF THE 19 CONDITIONS CONSIDERED. FIRST, WE ASSESSED WHETHER THE ASSOCIATIONS IDENTIFIED IN OUR STUDY WERE REPORTED IN PREVIOUS STUDIES. WE IDENTIFIED 69 ASSOCIATIONS BETWEEN CPGS AND THE PREVALENCE OF 4 CONDITIONS, OF WHICH 58 WERE NEWLY DESCRIBED. THE CONDITIONS WERE BREAST CANCER, CHRONIC KIDNEY DISEASE, ISCHEMIC HEART DISEASE, AND TYPE 2 DIABETES MELLITUS. WE ALSO UNCOVERED 64 CPGS THAT ASSOCIATED WITH THE INCIDENCE OF 2 DISEASE STATES (COPD AND TYPE 2 DIABETES), OF WHICH 56 WERE NOT REPORTED IN THE SURVEYED LITERATURE. SECOND, WE ASSESSED REPLICATION ACROSS EXISTING STUDIES, WHICH WAS DEFINED AS THE REPORTING OF AT LEAST 1 COMMON SITE IN >2 STUDIES THAT EXAMINED THE SAME CONDITION. ONLY 6/19 DISEASE STATES HAD EVIDENCE OF SUCH REPLICATION. THE LIMITATIONS OF THIS STUDY INCLUDE THE NONCONSIDERATION OF MEDICATION DATA AND A POTENTIAL LACK OF GENERALIZABILITY TO INDIVIDUALS THAT ARE NOT OF SCOTTISH AND EUROPEAN ANCESTRY. CONCLUSIONS: WE DISCOVERED OVER 100 ASSOCIATIONS BETWEEN BLOOD METHYLATION SITES AND COMMON DISEASE STATES, INDEPENDENTLY OF MAJOR CONFOUNDING RISK FACTORS, AND A NEED FOR GREATER STANDARDISATION AMONG EWAS ON HUMAN DISEASE. 2023