1 6311 123 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 2 497 27 ASSOCIATION BETWEEN BMI AND DNA METHYLATION IN BLOOD OR NORMAL ADULT BREAST TISSUE: A SYSTEMATIC REVIEW. BACKGROUND/AIM: SEVERAL STUDIES HAVE INVESTIGATED THE INFLUENCE OF OBESITY ON DNA METHYLATION (DNAM) TO FIND BIOMARKERS ASSOCIATED WITH THE DETECTION OF CHRONIC DISEASES, INCLUDING BREAST CANCER. THE AIM OF THE STUDY WAS TO SYSTEMATICALLY REVIEW STUDIES EXAMINING THE ASSOCIATION OF BODY MASS INDEX (BMI) AND DNAM IN BLOOD OR NORMAL BREAST TISSUE. MATERIALS AND METHODS: THREE SCIENTIFIC LITERATURE DATABASES (PUBMED, EMBASE AND WEB OF SCIENCE) WERE SCREENED UNTIL MAY 2018. RESULTS: TWENTY-FOUR STUDIES WERE INCLUDED ALONG WITH OURS IN WHICH WE INVESTIGATED THIS RELATION IN THE NORMAL BREAST TISSUE OF 40 BREAST CANCER PATIENTS. CONCLUSION: BMI-ASSOCIATED CPG SITES WERE HIGHLY VARIABLE WITH FEW IDENTIFIED IN LESS THAN HALF OF THE STUDIES. NEVERTHELESS, A FEW GENES POTENTIALLY ASSOCIATED WITH BMI WERE HIGHLIGHTED IN BLOOD (CPT1A, ABCG1, SREBF1 AND LGALS3BP) AND IN NORMAL BREAST TISSUE (PTPRN2 AND ABLIM2). THE VARIABILITY OF THE RESULTS COULD BE EXPLAINED BY THE TISSUE AND CELL-SPECIFICITY OF METHYLATION AND DIFFERENCES IN METHODOLOGY. 2020 3 1589 26 DNA METHYLATION PROFILING IN A CIGARETTE SMOKE-EXPOSED MOUSE MODEL OF AIRWAY INFLAMMATION. PURPOSE: DNA METHYLATION, A MAJOR EPIGENETIC MODIFICATION, HAS BEEN DOCUMENTED TO PLAY AN IMPORTANT ROLE IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). IN THIS STUDY, WE AIMED TO PROFILE THE DNA METHYLATION PATTERNS IN A MOUSE MODEL OF AIRWAY INFLAMMATION INDUCED BY CIGARETTE SMOKE (CS), A FOREMOST RISK FACTOR OF COPD. MATERIAL AND METHODS: TO ESTABLISH A MODEL OF AIRWAY INFLAMMATION, WILD-TYPE MICE WERE EXPOSED TO MAINSTREAM CS OR ROOM AIR FOR 2 HOURS TWICE DAILY, 6 DAYS PER WEEK FOR CONSECUTIVE 4 WEEKS. LUNG TISSUES OF THE MICE WERE COLLECTED FOR GENOME-WIDE DNA METHYLATION ANALYSIS BY LIQUID HYBRIDIZATION CAPTURE-BASED BISULFITE SEQUENCING, WHICH WERE USED FOR INTERSECTION ANALYSIS WITH GENE EXPRESSION BY CDNA MICROARRAY TO IDENTIFY CANDIDATE METHYLATED GENES. THEN, FUNCTIONAL ENRICHMENT ANALYSES WITH PROTEIN-PROTEIN INTERACTION (PPI) NETWORK REGARDING THESE GENES WERE CONDUCTED TO EXPLORE THE POTENTIAL MECHANISMS. RESULTS: AFTER 4-WEEK CS EXPOSURE, THE LEVEL OF DNA METHYLATION ACCOMPANIED BY A SUBACUTE AIRWAY INFLAMMATION WAS MARKEDLY ENHANCED, AND 2002 DIFFERENTIALLY METHYLATED GENES (DMGS) WERE ANNOTATED, INCLUDING 565 DMGS CONTAINED METHYLATIONS IN GENE PROMOTERS, WHICH WERE USED FOR INTERSECTION WITH THE DIFFERENTIALLY EXPRESSED GENES. THEN, 135 CANDIDATE METHYLATED GENES WERE FURTHER SELECTED BY THE INTERSECTION, AMONG WHICH 58 GENES WITH FUNCTIONAL METHYLATED MODIFICATION WERE FINALLY IDENTIFIED. FURTHER ANALYSES REVEALED CANDIDATE METHYLATED GENES WERE SIGNIFICANTLY ENRICHED IN A COMPLICATED NETWORK OF SIGNALS AND PROCESSES, INCLUDING INTERLEUKINS, TOLL-LIKE RECEPTORS, T-CELLS DIFFERENTIATION, OXIDATIVE STRESS, MAST CELLS ACTIVATION, STEM CELLS PROLIFERATION, ETC., AS WELL AS THE 58 FUNCTIONAL METHYLATED GENES WERE PARTIALLY LOCATED AT KEY POSITIONS IN PPI NETWORK, ESPECIALLY CXCL1, DDX58 AND JAK3. CONCLUSION: THIS STUDY SUGGESTS CS EXPOSURE SIGNIFICANTLY ENHANCES DNA METHYLATED LEVEL, AND THE POTENTIAL FUNCTIONAL METHYLATED GENES ARE CLOSELY RELATED TO COMPLICATED INFLAMMATORY-IMMUNE RESPONSES, WHICH MAY PROVIDE SOME NEW EXPERIMENTAL EVIDENCE IN UNDERSTANDING THE EPIGENETIC MECHANISMS OF CS-INDUCED AIRWAY INFLAMMATION IN COPD. 2022 4 2734 40 EXPLORING THE RELATIONSHIP BETWEEN DNA METHYLATION AGE MEASURES AND PSYCHONEUROLOGICAL SYMPTOMS IN WOMEN WITH EARLY-STAGE BREAST CANCER. PURPOSE: THE EPIGENETIC CLOCK HAS BEEN ACKNOWLEDGED AS AN INDICATOR FOR MOLECULAR AGING, BUT FEW STUDIES HAVE EXAMINED POSSIBLE ASSOCIATIONS OF DNA METHYLATION (DNAM) AGE OR AGE ACCELERATION (AA) WITH SYMPTOM BURDEN IN INDIVIDUALS WHO ARE TREATED FOR CANCER. THIS STUDY EXPLORED THE ASSOCIATION OF DNAM AGE OR AA WITH PSYCHONEUROLOGICAL (PN) SYMPTOMS, INCLUDING COGNITIVE IMPAIRMENT, FATIGUE, SLEEP DISTURBANCES, PAIN, AND DEPRESSIVE SYMPTOMS, IN BREAST CANCER SURVIVORS OVER A 2-YEAR PERIOD. METHODS: WE MEASURED PN SYMPTOMS USING RELIABLE INSTRUMENTS AND DNAM LEVELS BY INFINIUM HUMANMETHYLATION450K BEADCHIP (N = 72). DNAM AGE WAS CALCULATED BY THE HORVATH, GRIM, AND HANNUM-BASED INTRINSIC AND EXTRINSIC AGE ESTIMATIONS. AA WAS DEFINED BY THE RESIDUAL REGRESSING ESTIMATED EPIGENETIC AGE ON CHRONOLOGICAL AGE. MIXED REGRESSION MODELS WERE FITTED FOR AA AND CHANGES IN AA TO STUDY THE ASSOCIATION OVER TIME. SEPARATE LINEAR REGRESSION MODELS AND A MIXED-EFFECTS MODEL WERE FITTED FOR AA AT EACH TIME POINT. RESULTS: HORVATH-AA, GRIM-AA, AND EXTRINSIC EPIGENETIC AA WERE SIGNIFICANTLY CHANGED OVER TIME, WHILE INTRINSIC EPIGENETIC AA DID NOT EXHIBIT ANY TEMPORAL CHANGES. INCREASED AA WAS ASSOCIATED WITH GREATER ANXIETY AND FATIGUE, AS WELL AS WORSE COGNITIVE MEMORY, ADJUSTING FOR RACE, BMI, INCOME, CHEMOTHERAPY, RADIATION THERAPY, AND CHRONOLOGICAL AGE. INCREASED DNAM AGE WAS ASSOCIATED WITH GREATER ANXIETY OVER 2 YEARS. CONCLUSION: OUR FINDINGS SUGGEST DNAM AGE AND AA MAY BE ASSOCIATED WITH PN SYMPTOMS OVER THE COURSE OF CANCER TREATMENT AND SURVIVORSHIP. SOME PN SYMPTOMS MAY BE AMENABLE TO PREVENTIVE INTERVENTIONS TARGETED TO EPIGENETIC CLOCKS THAT INFLUENCE AGING-ASSOCIATED PROCESSES. 2022 5 1439 34 DIFFERENTIAL PLACENTAL CPG METHYLATION IS ASSOCIATED WITH CHRONIC LUNG DISEASE OF PREMATURITY. BACKGROUND: CHRONIC LUNG DISEASE (CLD) IS THE MOST COMMON PULMONARY MORBIDITY IN EXTREMELY PRETERM INFANTS. IT IS UNCLEAR TO WHAT EXTENT PRENATAL EXPOSURES INFLUENCE THE RISK OF CLD. EPIGENETIC VARIATION IN PLACENTA DNA METHYLATION MAY BE ASSOCIATED WITH DIFFERENTIAL RISK OF CLD, AND THESE ASSOCIATIONS MAY BE DEPENDENT UPON SEX. METHODS: DATA WERE OBTAINED FROM A MULTI-CENTER COHORT OF INFANTS BORN EXTREMELY PRETERM (<28 WEEKS' GESTATION) AND AN EPIGENOME-WIDE APPROACH WAS USED TO IDENTIFY ASSOCIATIONS BETWEEN PLACENTAL DNA METHYLATION AND CLD (N = 423). ASSOCIATIONS WERE EVALUATED USING ROBUST LINEAR REGRESSION ADJUSTING FOR COVARIATES, WITH A FALSE DISCOVERY RATE OF 0.05. ANALYSES STRATIFIED BY SEX WERE USED TO ASSESS DIFFERENCES IN METHYLATION-CLD ASSOCIATIONS. RESULTS: CLD WAS ASSOCIATED WITH DIFFERENTIAL METHYLATION AT 49 CPG SITES REPRESENTING 46 GENES IN THE PLACENTA. CLD WAS ASSOCIATED WITH DIFFERENTIAL METHYLATION OF PROBES WITHIN GENES RELATED TO PATHWAYS INVOLVED IN FETAL LUNG DEVELOPMENT, SUCH AS P53 SIGNALING AND MYO-INOSITOL BIOSYNTHESIS. ASSOCIATIONS BETWEEN CPG METHYLATION AND CLD DIFFERED BY SEX. CONCLUSIONS: DIFFERENTIAL PLACENTAL METHYLATION WITHIN GENES WITH KEY ROLES IN FETAL LUNG DEVELOPMENT MAY REFLECT COMPLEX CELL SIGNALING BETWEEN THE PLACENTA AND FETUS WHICH MEDIATE CLD RISK. THESE PATHWAYS APPEAR TO BE DISTINCT BASED ON FETAL SEX. IMPACT: IN EXTREMELY PRETERM INFANTS, DIFFERENTIAL METHYLATION OF CPG SITES WITHIN PLACENTAL GENES INVOLVED IN PATHWAYS RELATED TO CELL SIGNALING, OXIDATIVE STRESS, AND TROPHOBLAST INVASION IS ASSOCIATED WITH CHRONIC LUNG DISEASE OF PREMATURITY. DNA METHYLATION PATTERNS ASSOCIATED WITH CHRONIC LUNG DISEASE WERE DISTINCTLY BASED ON FETAL SEX, SUGGESTING A POTENTIAL MECHANISM UNDERLYING DIMORPHIC PHENOTYPES. MECHANISMS RELATED TO FETAL HYPOXIA AND PLACENTAL MYO-INOSITOL SIGNALING MAY PLAY A ROLE IN FETAL LUNG PROGRAMMING AND THE DEVELOPMENTAL ORIGINS OF CHRONIC LUNG DISEASE. CONTINUED RESEARCH OF THE RELATIONSHIP BETWEEN THE PLACENTAL EPIGENOME AND CHRONIC LUNG DISEASE COULD INFORM EFFORTS TO AMELIORATE OR PREVENT THIS CONDITION. 2022 6 2418 32 EPIGENETIC SIGNATURE OF CHRONIC LOW BACK PAIN IN HUMAN T CELLS. OBJECTIVE: DETERMINE IF CHRONIC LOW BACK PAIN (LBP) IS ASSOCIATED WITH DNA METHYLATION SIGNATURES IN HUMAN T CELLS THAT WILL REVEAL NOVEL MECHANISMS AND POTENTIAL THERAPEUTIC TARGETS AND EXPLORE THE FEASIBILITY OF EPIGENETIC DIAGNOSTIC MARKERS FOR PAIN-RELATED PATHOPHYSIOLOGY. METHODS: GENOME-WIDE DNA METHYLATION ANALYSIS OF 850,000 CPG SITES IN WOMEN AND MEN WITH CHRONIC LBP AND PAIN-FREE CONTROLS WAS PERFORMED. T CELLS WERE ISOLATED (DISCOVERY COHORT, N = 32) AND USED TO IDENTIFY DIFFERENTIALLY METHYLATED CPG SITES, AND GENE ONTOLOGIES AND MOLECULAR PATHWAYS WERE IDENTIFIED. A POLYGENIC DNA METHYLATION SCORE FOR LBP WAS GENERATED IN BOTH WOMEN AND MEN. VALIDATION WAS PERFORMED IN AN INDEPENDENT COHORT (VALIDATION COHORT, N = 63) OF CHRONIC LBP AND HEALTHY CONTROLS. RESULTS: ANALYSIS WITH THE DISCOVERY COHORT REVEALED A TOTAL OF 2,496 AND 419 DIFFERENTIALLY METHYLATED CPGS IN WOMEN AND MEN, RESPECTIVELY. IN WOMEN, MOST OF THESE SITES WERE HYPOMETHYLATED AND ENRICHED IN GENES WITH FUNCTIONS IN THE EXTRACELLULAR MATRIX, IN THE IMMUNE SYSTEM (IE, CYTOKINES), OR IN EPIGENETIC PROCESSES. IN MEN, A UNIQUE CHRONIC LBP DNA METHYLATION SIGNATURE WAS IDENTIFIED CHARACTERIZED BY SIGNIFICANT ENRICHMENT FOR GENES FROM THE MAJOR HISTOCOMPATIBILITY COMPLEX. SEX-SPECIFIC POLYGENIC DNA METHYLATION SCORES WERE GENERATED TO ESTIMATE THE PAIN STATUS OF EACH INDIVIDUAL AND CONFIRMED IN THE VALIDATION COHORT USING PYROSEQUENCING. CONCLUSION: THIS STUDY REVEALS SEX-SPECIFIC DNA METHYLATION SIGNATURES IN HUMAN T CELLS THAT DISCRIMINATES CHRONIC LBP PARTICIPANTS FROM HEALTHY CONTROLS. 2021 7 2281 31 EPIGENETIC REGULATION IN EARLY CHILDHOOD: A MINIATURIZED AND VALIDATED METHOD TO ASSESS HISTONE ACETYLATION. INTRODUCTION: CHRONIC INFLAMMATORY DISEASES INCLUDING ALLERGIES AND ASTHMA ARE THE RESULT OF COMPLEX INTERACTIONS BETWEEN GENES AND ENVIRONMENTAL FACTORS. EPIGENETIC MECHANISMS COMPRISE A SET OF BIOCHEMICAL REACTIONS THAT REGULATE GENE EXPRESSION. IN ORDER TO UNDERSTAND THE CAUSE-EFFECT RELATIONSHIP BETWEEN ENVIRONMENTAL EXPOSURES AND DISEASE DEVELOPMENT, METHODS CAPABLE OF ASSESSING EPIGENETIC REGULATION (ALSO) IN LARGE COHORTS ARE NEEDED. METHODS: FOR THIS PURPOSE, WE DEVELOPED AND EVALUATED A MINIATURIZED CHROMATIN IMMUNOPRECIPITATION (CHIP) ASSAY ALLOWING FOR A COST-EFFECTIVE ASSESSMENT OF HISTONE ACETYLATION OF CANDIDATE GENES IN A QUANTITATIVE FASHION. THIS METHOD WAS THEN APPLIED TO ASSESS H3 AND H4 HISTONE ACETYLATION CHANGES IN CORD BLOOD (CB) SAMPLES FROM AN ESTABLISHED COHORT OF AUSTRALIAN CHILDREN EXPOSED IN THE FETAL PERIOD TO EITHER VERY LOW OR VERY HIGH LEVELS OF MATERNAL FOLATE. RESULTS: OUR CHIP ASSAY WAS VALIDATED FOR A MINIMUM REQUIREMENT OF 1 X 105 TARGET CELLS (E.G. CD4+ T CELLS). VERY HIGH LEVELS OF MATERNAL FOLATE WERE SIGNIFICANTLY ASSOCIATED WITH INCREASED H3/H4 ACETYLATION AT GATA3 AND/OR IL9 PROMOTER REGIONS IN CD4+ T CELLS IN CB. CONCLUSION: WE DEVELOPED A CHIP METHOD ALLOWING RELIABLE ASSESSMENT OF H3/H4 ACETYLATION USING 1 X 105 CELLS ONLY. PRACTICAL APPLICATION OF THIS ASSAY DEMONSTRATED AN ASSOCIATION BETWEEN HIGH MATERNAL FOLATE EXPOSURE AND INCREASED HISTONE ACETYLATION, CORRESPONDING TO A MORE TRANSCRIPTIONALLY PERMISSIVE CHROMATIN STATUS IN THE PROMOTER REGIONS OF SOME TH2-RELATED GENES. 2015 8 3503 25 IDENTIFICATION OF POTENTIAL DIFFERENTIALLY METHYLATED GENE-RELATED BIOMARKERS IN ENDOMETRIOSIS. AIM: TO IDENTIFY EPIGENETIC ALTERATIONS OF DIFFERENTIALLY EXPRESSED GENES AND SCREEN OUT TARGETED THERAPEUTIC DRUGS IN ENDOMETRIOSIS. METHODS: BASED ON THE GENE EXPRESSION OMNIBUS DATABASE AND A SERIES OF BIOLOGICAL INFORMATION ANALYSIS TOOLS, SUPPLEMENTED BY VALIDATION OF CLINICAL SAMPLES, ABERRANT DNA METHYLATION-DRIVEN GENES AND THEIR FUNCTIONS WERE EXPLORED, AS WELL AS POSSIBLE TARGETED DRUGS. RESULTS: THIS STUDY SCREENED OUT A RANGE OF DNA METHYLATION-DRIVEN GENES THAT WERE ASSOCIATED WITH POWERFUL PROPERTIES AND CORRESPONDING PATHWAYS. AMONG THEM, BDNF AND CCL2 WERE KEY GENES IN THE DEVELOPMENT OF ENDOMETRIOSIS. FOUR CHEMICAL AGENTS HAVE BEEN FLAGGED AS POTENTIAL TREATMENTS FOR ENDOMETRIOSIS. CONCLUSION: THESE CANDIDATE GENES AND SMALL-MOLECULE AGENTS MAY BE FURTHER EXPLORED AS POTENTIAL TARGETS AND DRUGS FOR ENDOMETRIOSIS DIAGNOSIS AND THERAPY, RESPECTIVELY. 2022 9 1345 37 DETECTION OF DIFFERENTIALLY METHYLATED REGIONS USING BAYES FACTOR FOR ORDINAL GROUP RESPONSES. RESEARCHERS IN GENOMICS ARE INCREASINGLY INTERESTED IN EPIGENETIC FACTORS SUCH AS DNA METHYLATION, BECAUSE THEY PLAY AN IMPORTANT ROLE IN REGULATING GENE EXPRESSION WITHOUT CHANGES IN THE DNA SEQUENCE. THERE HAVE BEEN SIGNIFICANT ADVANCES IN DEVELOPING STATISTICAL METHODS TO DETECT DIFFERENTIALLY METHYLATED REGIONS (DMRS) ASSOCIATED WITH BINARY DISEASE STATUS. MOST OF THESE METHODS ARE BEING DEVELOPED FOR DETECTING DIFFERENTIAL METHYLATION RATES BETWEEN CASES AND CONTROLS. WE CONSIDER MULTIPLE SEVERITY LEVELS OF DISEASE, AND DEVELOP A BAYESIAN STATISTICAL METHOD TO DETECT THE REGION WITH INCREASING (OR DECREASING) METHYLATION RATES AS THE DISEASE SEVERITY INCREASES. PATIENTS ARE CLASSIFIED INTO MORE THAN TWO GROUPS, BASED ON THE DISEASE SEVERITY (E.G., STAGES OF CANCER), AND DMRS ARE DETECTED BY USING MOVING WINDOWS ALONG THE GENOME. WITHIN EACH WINDOW, THE BAYES FACTOR IS CALCULATED TO TEST THE HYPOTHESIS OF MONOTONIC INCREASE IN METHYLATION RATES CORRESPONDING TO SEVERITY OF THE DISEASE VERSUS NO DIFFERENCE. A MIXED-EFFECT MODEL IS USED TO INCORPORATE THE CORRELATION OF METHYLATION RATES OF NEARBY CPG SITES IN THE REGION. RESULTS FROM EXTENSIVE SIMULATION INDICATE THAT OUR PROPOSED METHOD IS STATISTICALLY VALID AND REASONABLY POWERFUL. WE DEMONSTRATE OUR APPROACH ON A BISULFITE SEQUENCING DATASET FROM A CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) STUDY. 2019 10 6027 27 THE BLOOD DNA METHYLATION CLOCK GRIMAGE IS A ROBUST SURROGATE FOR AIRWAY EPITHELIA AGING. ONE KEY FEATURE OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS THAT ITS PREVALENCE INCREASES EXPONENTIALLY WITH AGE. DNA METHYLATION CLOCKS HAVE BECOME POWERFUL BIOMARKERS TO DETECT ACCELERATED AGING IN A VARIETY OF DISEASES AND CAN HELP PROGNOSE OUTCOMES IN SEVERE COPD. THIS STUDY INVESTIGATED WHICH DNA METHYLATION CLOCK COULD BEST REFLECT AIRWAY EPIGENETIC AGE WHEN USED IN MORE ACCESSIBLE BLOOD SAMPLES. OUR ANALYSES SHOWED THAT OUT OF SIX DNA METHYLATION CLOCKS INVESTIGATED, DNAMGRIMAGE DEMONSTRATED THE STRONGEST CORRELATION AND THE SMALLEST DIFFERENCE BETWEEN THE AIRWAY EPITHELIUM AND BLOOD. OUR FINDINGS SUGGESTS THAT BLOOD DNAMGRIMAGE ACCURATELY REFLECTS AIRWAY EPIGENETIC AGE OF INDIVIDUALS AND THAT ITS ELEVATION IS HIGHLY ASSOCIATED WITH COPD. 2022 11 3079 42 GENOME-WIDE METHYLATION AND EXPRESSION ANALYSES REVEAL THE EPIGENETIC LANDSCAPE OF IMMUNE-RELATED DISEASES FOR TOBACCO SMOKING. BACKGROUND: SMOKING IS A MAJOR CAUSAL RISK FACTOR FOR LUNG CANCER, CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD), CARDIOVASCULAR DISEASE (CVD), AND IS THE MAIN PREVENTABLE CAUSE OF DEATHS IN THE WORLD. THE COMPONENTS OF CIGARETTE SMOKE ARE INVOLVED IN IMMUNE AND INFLAMMATORY PROCESSES, WHICH MAY INCREASE THE PREVALENCE OF CIGARETTE SMOKE-RELATED DISEASES. HOWEVER, THE UNDERLYING MOLECULAR MECHANISMS LINKING SMOKING AND DISEASES HAVE NOT BEEN WELL EXPLORED. THIS STUDY WAS AIMED TO DEPICT A GLOBAL MAP OF DNA METHYLATION AND GENE EXPRESSION CHANGES INDUCED BY TOBACCO SMOKING AND TO EXPLORE THE MOLECULAR MECHANISMS BETWEEN SMOKING AND HUMAN DISEASES THROUGH WHOLE-GENOME BISULFITE SEQUENCING (WGBS) AND RNA-SEQUENCING (RNA-SEQ). RESULTS: WE PERFORMED WGBS ON 72 SAMPLES (36 SMOKERS AND 36 NONSMOKERS) AND RNA-SEQ ON 75 SAMPLES (38 SMOKERS AND 37 NONSMOKERS), AND CYTOKINE IMMUNOASSAY ON PLASMA FROM 22 MALES (9 SMOKERS AND 13 NONSMOKERS) WHO WERE RECRUITED FROM THE CITY OF JINCHENG IN CHINA. BY COMPARING THE DATA OF THE TWO GROUPS, WE DISCOVERED A GENOME-WIDE METHYLATION LANDSCAPE OF DIFFERENTIALLY METHYLATED REGIONS (DMRS) ASSOCIATED WITH SMOKING. FUNCTIONAL ENRICHMENT ANALYSES REVEALED THAT BOTH SMOKING-RELATED HYPER-DMR GENES (DMGS) AND HYPO-DMGS WERE RELATED TO SYNAPSE-RELATED PATHWAYS, WHEREAS THE HYPO-DMGS WERE SPECIFICALLY RELATED TO CANCER AND ADDICTION. THE DIFFERENTIALLY EXPRESSED GENES (DEGS) REVEALED BY RNA-SEQ ANALYSIS WERE SIGNIFICANTLY ENRICHED IN THE "IMMUNOSUPPRESSION" PATHWAY. CORRELATION ANALYSIS OF DMRS WITH THEIR CORRESPONDING GENE EXPRESSION SHOWED THAT GENES AFFECTED BY TOBACCO SMOKING WERE MOSTLY RELATED TO IMMUNE SYSTEM DISEASES. FINALLY, BY COMPARING CYTOKINE CONCENTRATIONS BETWEEN SMOKERS AND NONSMOKERS, WE FOUND THAT VASCULAR ENDOTHELIAL GROWTH FACTOR (VEGF) WAS SIGNIFICANTLY UPREGULATED IN SMOKERS. CONCLUSIONS: IN SUM, WE FOUND THAT SMOKING-INDUCED DMRS HAVE DIFFERENT DISTRIBUTION PATTERNS IN HYPERMETHYLATED AND HYPOMETHYLATED AREAS BETWEEN SMOKERS AND NONSMOKERS. WE FURTHER IDENTIFIED AND VERIFIED SMOKING-RELATED DMGS AND DEGS THROUGH MULTI-OMICS INTEGRATION ANALYSIS OF DNA METHYLOME AND TRANSCRIPTOME DATA. THESE FINDINGS PROVIDE US A COMPREHENSIVE GENOMIC MAP OF THE MOLECULAR CHANGES INDUCED BY SMOKING WHICH WOULD ENHANCE OUR UNDERSTANDING OF THE HARMS OF SMOKING AND ITS RELATIONSHIP WITH DISEASES. 2021 12 5882 39 SYSTEMATIC REVIEW OF LUNG FUNCTION AND COPD WITH PERIPHERAL BLOOD DNA METHYLATION IN POPULATION BASED STUDIES. BACKGROUND: EPIGENETIC VARIATIONS IN PERIPHERAL BLOOD HAVE POTENTIAL AS BIOMARKERS FOR DISEASE. THIS SYSTEMATIC REVIEW ASSESSES THE ASSOCIATION OF LUNG FUNCTION AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) WITH DNA METHYLATION PROFILES IN PERIPHERAL BLOOD FROM POPULATION-BASED STUDIES. METHODS: ONLINE DATABASES MEDLINE, EMBASE, AND WEB OF SCIENCE WERE SEARCHED. GOOGLE SCHOLAR WAS SEARCHED TO IDENTIFY GREY LITERATURE. AFTER REMOVING DUPLICATE ARTICLES, 1155 ARTICLES WERE INDEPENDENTLY SCREENED BY TWO INVESTIGATORS. PEER REVIEWED REPORTS ON POPULATION-BASED STUDIES THAT EXAMINED PERIPHERAL BLOOD DNA METHYLATION IN PARTICIPANTS WITH MEASURED LUNG FUNCTION (FEV1, FEV1/FVC RATIO) OR KNOWN COPD STATUS WERE SELECTED FOR FULL-TEXT REVIEW. SIX ARTICLES WERE SUITABLE FOR INCLUSION. INFORMATION REGARDING STUDY CHARACTERISTICS, DESIGNS, METHODOLOGIES AND CONCLUSIONS WAS EXTRACTED. A NARRATIVE SYNTHESIS WAS PERFORMED BASED ON PUBLISHED RESULTS. RESULTS: THREE OF THE SIX ARTICLES ASSESSED THE ASSOCIATION OF COPD WITH DNA METHYLATION, AND TWO OF THESE ALSO INCLUDED ASSOCIATIONS WITH LUNG FUNCTION. OVERALL, FIVE REPORTS EXAMINED THE ASSOCIATION OF LUNG FUNCTION WITH DNA METHYLATION PROFILES. FIVE OF THE SIX ARTICLES REPORTED 'SIGNIFICANT' RESULTS. HOWEVER, NO CONSISTENT CPG SITES WERE IDENTIFIED ACROSS STUDIES FOR COPD STATUS OR LUNG FUNCTION VALUES. CONCLUSIONS: DNA METHYLATION PATTERNS IN PERIPHERAL BLOOD FROM INDIVIDUALS WITH REDUCED LUNG FUNCTION OR COPD MAY BE DIFFERENT TO THOSE IN PEOPLE WITH NORMAL LUNG FUNCTION. HOWEVER, THIS SYSTEMATIC REVIEW DID NOT FIND ANY CONSISTENT ASSOCIATIONS OF LUNG FUNCTION OR COPD WITH DIFFERENTIALLY METHYLATED CPG SITES. LARGE STUDIES WITH A LONGITUDINAL DESIGN TO ADDRESS REVERSE CAUSALITY MAY PROVE A MORE FRUITFUL AREA OF RESEARCH. TRIAL REGISTRATION: PROSPERO 2016: CRD42016037352 . 2017 13 6790 23 [DNA METHYLATION ANALYSIS IN ENVIRONMENTAL AND OCCUPATIONAL CANCER RESEARCH]. THE PRESENT PAPER REVIEWS RECENT LABORATORY METHODS AND EXPERIMENTAL EVIDENCE CONCERNING EPIGENETIC BIOMARKERS INVOLVED IN CARCINOGENESIS MECHANISMS. WE INTRODUCE DNA METHYLATION AND ITS ROLE IN GENE EXPRESSION CONTROL. DNA METHYLATION ANALYSIS MAY ALLOW TO IDENTIFY EARLY CHANGES LEADING TO CANCER AND OTHER CHRONIC DISEASES. WE DESCRIBE HERE STRATEGIES FOR LABORATORY ANALYSES AND THEIR POSSIBLE APPLICATIONS. WE EXAMINE RESULTS FROM RECENT EXPERIMENTAL STUDIES SUGGESTING THAT THE EFFECTS OF CERTAIN OCCUPATIONAL AGENTS ARE MEDIATED BY ALTERATIONS IN DNA METHYLATION. PLANNING AND CONDUCTING INVESTIGATIONS ON EXPOSED HUMAN SUBJECTS WILL ALLOW TO VERIFY WHETHER DNA METHYLATION CHANGES IDENTIFIED IN ANIMAL AND IN-VITRO STUDIES MAY BE USED AS EARLY-EFFECT AND SUSCEPTIBILITY BIOMARKERS. DNA METHYLATION ANALYSIS HAS THE POTENTIAL FOR FUTURE APPLICATIONS IN RISK ASSESSMENT AND PREVENTION PROGRAMS CONDUCTED ON SUBJECTS EXPOSED TO HUMAN CARCINOGENS. 2005 14 6720 35 VITAMIN D METABOLISM GENES ARE DIFFERENTIALLY METHYLATED IN INDIVIDUALS WITH CHRONIC KNEE PAIN. CONTEXT: RECENT EVIDENCE SUGGESTS THAT VITAMIN D MAY INTERACT WITH THE EPIGENOME AND PLAY A ROLE IN THE PAIN EXPERIENCE. IN ORDER FOR PROPER FUNCTIONING TO OCCUR, THERE MUST BE AN ADEQUATE LEVEL OF VITAMIN D PRESENT, MADE POSSIBLE BY ENZYMATIC REACTIONS THAT ALLOW VITAMIN D TO BE BIOLOGICALLY ACTIVE. THE PURPOSE OF THIS STUDY WAS TO EXPLORE THE EPIGENETIC LANDSCAPE OF GENES INVOLVED IN VITAMIN D METABOLISM IN INDIVIDUALS WITH AND WITHOUT CHRONIC KNEE PAIN. PROCEDURES: COMMUNITY-DWELLING INDIVIDUALS RECRUITED AS PART OF A LARGER STUDY FOCUSED ON KNEE PAIN PROVIDED DEMOGRAPHIC, CLINICAL AND PAIN-RELATED INFORMATION, AS WELL AS AN INTRAVENOUS BLOOD SAMPLE TO DETERMINE DNA METHYLATION LEVELS AT CPG SITES. MAIN FINDINGS: THERE WERE DIFFERENCES IN DNA METHYLATION BETWEEN THOSE WITH AND WITHOUT PAIN IN GENES THAT CODE FOR ENZYMES RELATED TO VITAMIN D METABOLISM: CYP24A1 (24-HYDROXYLASE) AND CYP27B1 (1-?-HYDROXYLASE). THERE WAS ALSO HYPERMETHYLATION ON THE GENE THAT CODES FOR THE VITAMIN D RECEPTOR (VDR). PRINCIPAL CONCLUSIONS: THE PRESENCE OF CHRONIC PAIN IS ASSOCIATED WITH EPIGENETIC MODIFICATIONS IN GENES RESPONSIBLE FOR THE EXPRESSION OF ENZYMES INVOLVED IN VITAMIN D METABOLISM AND CELLULAR FUNCTION. THESE RESULTS LAY GROUNDWORK IN UNDERSTANDING THE MECHANISM UNDERLYING THE ASSOCIATION BETWEEN VITAMIN D AND CHRONIC PAIN. 2023 15 3652 34 INDIVIDUAL DNA METHYLATION PATTERN SHIFTS IN NANOPARTICLES-EXPOSED WORKERS ANALYZED IN FOUR CONSECUTIVE YEARS. A DNA METHYLATION PATTERN REPRESENTS AN ORIGINAL PLAN OF THE FUNCTION SETTINGS OF INDIVIDUAL CELLS AND TISSUES. THE BASIC STRATEGIES OF ITS DEVELOPMENT AND CHANGES DURING THE HUMAN LIFETIME ARE KNOWN, BUT THE DETAILS RELATED TO ITS MODIFICATION OVER THE YEARS ON AN INDIVIDUAL BASIS HAVE NOT YET BEEN STUDIED. MOREOVER, CURRENT EVIDENCE SHOWS THAT ENVIRONMENTAL EXPOSURE COULD GENERATE CHANGES IN DNA METHYLATION SETTINGS AND, SUBSEQUENTLY, THE FUNCTION OF GENES. IN THIS STUDY, WE ANALYZED THE EFFECT OF CHRONIC EXPOSURE TO NANOPARTICLES (NP) IN OCCUPATIONALLY EXPOSED WORKERS REPEATEDLY SAMPLED IN FOUR CONSECUTIVE YEARS (2016-2019). A DETAILED METHYLATION PATTERN ANALYSIS OF 14 PERSONS (10 EXPOSED AND 4 CONTROLS) WAS PERFORMED ON AN INDIVIDUAL BASIS. A MICROARRAY-BASED APPROACH USING CHIPS, ALLOWING THE ASSESSMENT OF MORE THAN 850 K CPG LOCI, WAS USED. INDIVIDUAL DNA METHYLATION PATTERNS WERE COMPARED BY PRINCIPAL COMPONENT ANALYSIS (PCA). THE RESULTS SHOW THE SHIFT IN DNA METHYLATION PATTERNS IN INDIVIDUAL YEARS IN ALL THE EXPOSED AND CONTROL SUBJECTS. THE OVERALL RANGE OF DIFFERENCES VARIED BETWEEN THE YEARS IN INDIVIDUAL PERSONS. THE DIFFERENCES BETWEEN THE FIRST AND LAST YEAR OF EXAMINATION (A THREE-YEAR TIME PERIOD) SEEM TO BE CONSISTENTLY GREATER IN THE NP-EXPOSED SUBJECTS IN COMPARISON WITH THE CONTROLS. THE SELECTED 14 MOST DIFFERENTLY METHYLATED CG LOCI WERE RELATIVELY STABLE IN THE CHRONICALLY EXPOSED SUBJECTS. IN SUMMARY, THE SPECIFIC TYPE OF LONG-TERM EXPOSURE CAN CONTRIBUTE TO THE FIXING OF RELEVANT EPIGENETIC CHANGES RELATED TO A SPECIFIC ENVIRONMENT AS, E.G., NP INHALATION. 2021 16 70 34 A METHOD TO DETECT DIFFERENTIALLY METHYLATED LOCI WITH NEXT-GENERATION SEQUENCING. EPIGENETIC CHANGES, ESPECIALLY DNA METHYLATION AT CPG LOCI HAVE IMPORTANT IMPLICATIONS IN CANCER AND OTHER COMPLEX DISEASES. WITH THE DEVELOPMENT OF NEXT-GENERATION SEQUENCING (NGS), IT IS FEASIBLE TO GENERATE DATA TO INTERROGATE THE DIFFERENCE IN METHYLATION STATUS FOR GENOME-WIDE LOCI USING CASE-CONTROL DESIGN. HOWEVER, A PROPER AND EFFICIENT STATISTICAL TEST IS LACKING. THERE ARE SEVERAL CHALLENGES. FIRST, UNLIKE METHYLATION EXPERIMENTS USING MICROARRAYS, WHERE THERE IS ONE MEASURE OF METHYLATION FOR ONE INDIVIDUAL AT A PARTICULAR CPG SITE, HERE WE HAVE THE COUNTS OF METHYLATION ALLELE AND UNMETHYLATION ALLELE FOR EACH INDIVIDUAL. SECOND, DUE TO THE NATURE OF SAMPLE PREPARATION, THE MEASURED METHYLATION REFLECTS THE METHYLATION STATUS OF A MIXTURE OF CELLS INVOLVED IN SAMPLE PREPARATION. THEREFORE, THE UNDERLYING DISTRIBUTION OF THE MEASURED METHYLATION LEVEL IS UNKNOWN, AND A ROBUST TEST IS MORE DESIRABLE THAN PARAMETRIC APPROACH. THIRD, CURRENTLY NGS MEASURES METHYLATION AT OVER 2 MILLION CPG SITES. ANY STATISTICAL TESTS HAVE TO BE COMPUTATIONALLY EFFICIENT IN ORDER TO BE APPLIED TO THE NGS DATA. TAKING THESE CHALLENGES INTO ACCOUNT, WE PROPOSE A TEST FOR DIFFERENTIAL METHYLATION BASED ON CLUSTERED DATA ANALYSIS BY MODELING THE METHYLATION COUNTS. WE PERFORMED SIMULATIONS TO SHOW THAT IT IS ROBUST UNDER SEVERAL DISTRIBUTIONS FOR THE MEASURED METHYLATION LEVELS. IT HAS GOOD POWER AND IS COMPUTATIONALLY EFFICIENT. FINALLY, WE APPLY THE TEST TO OUR NGS DATA ON CHRONIC LYMPHOCYTIC LEUKEMIA. THE RESULTS INDICATE THAT IT IS A PROMISING AND PRACTICAL TEST. 2013 17 2920 39 GENE-SET ANALYSIS IS SEVERELY BIASED WHEN APPLIED TO GENOME-WIDE METHYLATION DATA. MOTIVATION: DNA METHYLATION IS AN EPIGENETIC MARK THAT CAN STABLY REPRESS GENE EXPRESSION. BECAUSE OF ITS BIOLOGICAL AND CLINICAL SIGNIFICANCE, SEVERAL METHODS HAVE BEEN DEVELOPED TO COMPARE GENOME-WIDE PATTERNS OF METHYLATION BETWEEN GROUPS OF SAMPLES. THE APPLICATION OF GENE SET ANALYSIS TO IDENTIFY RELEVANT GROUPS OF GENES THAT ARE ENRICHED FOR DIFFERENTIALLY METHYLATED GENES IS OFTEN A MAJOR COMPONENT OF THE ANALYSIS OF THESE DATA. THIS CAN BE USED, FOR EXAMPLE, TO IDENTIFY PROCESSES OR PATHWAYS THAT ARE PERTURBED IN DISEASE DEVELOPMENT. WE SHOW THAT GENE-SET ANALYSIS, AS IT IS TYPICALLY APPLIED TO GENOME-WIDE METHYLATION ASSAYS, IS SEVERELY BIASED AS A RESULT OF DIFFERENCES IN THE NUMBERS OF CPG SITES ASSOCIATED WITH DIFFERENT CLASSES OF GENES AND GENE PROMOTERS. RESULTS: WE DEMONSTRATE THIS BIAS USING PUBLISHED DATA FROM A STUDY OF DIFFERENTIAL CPG ISLAND METHYLATION IN LUNG CANCER AND A DATASET WE GENERATED TO STUDY METHYLATION CHANGES IN PATIENTS WITH LONG-STANDING ULCERATIVE COLITIS. WE SHOW THAT SEVERAL OF THE GENE SETS THAT SEEM ENRICHED WOULD ALSO BE IDENTIFIED WITH RANDOMIZED DATA. WE SUGGEST TWO EXISTING APPROACHES THAT CAN BE ADAPTED TO CORRECT THE BIAS. ACCOUNTING FOR THE BIAS IN THE LUNG CANCER AND ULCERATIVE COLITIS DATASETS PROVIDES NOVEL BIOLOGICAL INSIGHTS INTO THE ROLE OF METHYLATION IN CANCER DEVELOPMENT AND CHRONIC INFLAMMATION, RESPECTIVELY. OUR RESULTS HAVE SIGNIFICANT IMPLICATIONS FOR MANY PREVIOUS GENOME-WIDE METHYLATION STUDIES THAT HAVE DRAWN CONCLUSIONS ON THE BASIS OF SUCH STRONGLY BIASED ANALYSIS. CONTACT: CATHAL.SEOIGHE@NUIGALWAY.IE SUPPLEMENTARY INFORMATION: SUPPLEMENTARY DATA ARE AVAILABLE AT BIOINFORMATICS ONLINE. 2013 18 1580 30 DNA METHYLATION PROFILES ARE ASSOCIATED WITH COMPLEX REGIONAL PAIN SYNDROME AFTER TRAUMATIC INJURY. FACTORS CONTRIBUTING TO DEVELOPMENT OF COMPLEX REGIONAL PAIN SYNDROME (CRPS) ARE NOT FULLY UNDERSTOOD. THIS STUDY EXAMINED POSSIBLE EPIGENETIC MECHANISMS THAT MAY CONTRIBUTE TO CRPS AFTER TRAUMATIC INJURY. DNA METHYLATION PROFILES WERE COMPARED BETWEEN INDIVIDUALS DEVELOPING CRPS (N = 9) AND THOSE DEVELOPING NON-CRPS NEUROPATHIC PAIN (N = 38) AFTER UNDERGOING AMPUTATION FOLLOWING MILITARY TRAUMA. LINEAR MODELS FOR MICROARRAY (LIMMA) ANALYSES REVEALED 48 DIFFERENTIALLY METHYLATED CYTOSINE-PHOSPHATE-GUANINE DINUCLEOTIDE (CPG) SITES BETWEEN GROUPS (UNADJUSTED P'S < 0.005), WITH THE TOP GENE COL11A1 MEETING BONFERRONI-ADJUSTED P < 0.05. THE SECOND LARGEST DIFFERENTIAL METHYLATION WAS OBSERVED FOR THE HLA-DRB6 GENE, AN IMMUNE-RELATED GENE LINKED PREVIOUSLY TO CRPS IN A SMALL GENE EXPRESSION STUDY. FOR ALL BUT 7 OF THE SIGNIFICANT CPG SITES, THE CRPS GROUP WAS HYPOMETHYLATED. NUMEROUS FUNCTIONAL GENE ONTOLOGY-BIOLOGICAL PROCESS CATEGORIES WERE SIGNIFICANTLY ENRICHED (FALSE DISCOVERY RATE-ADJUSTED Q VALUE <0.15), INCLUDING MULTIPLE IMMUNE-RELATED CATEGORIES (EG, ACTIVATION OF IMMUNE RESPONSE, IMMUNE SYSTEM DEVELOPMENT, REGULATION OF IMMUNE SYSTEM PROCESSES, AND ANTIGEN PROCESSING AND PRESENTATION). DIFFERENTIALLY METHYLATED GENES WERE MORE HIGHLY CONNECTED IN HUMAN PROTEIN-PROTEIN NETWORKS THAN EXPECTED BY CHANCE (P < 0.05), SUPPORTING THE BIOLOGICAL RELEVANCE OF THE FINDINGS. RESULTS WERE VALIDATED IN AN INDEPENDENT SAMPLE LINKING A DNA BIOBANK WITH ELECTRONIC HEALTH RECORDS (N = 126 CRPS PHENOTYPE, N = 19,768 NON-CRPS CHRONIC PAIN PHENOTYPE). ANALYSES USING PREDIXCAN METHODOLOGY INDICATED DIFFERENCES IN THE GENETICALLY DETERMINED COMPONENT OF GENE EXPRESSION IN 7 OF 48 GENES IDENTIFIED IN METHYLATION ANALYSES (P'S < 0.02). RESULTS SUGGEST THAT IMMUNE- AND INFLAMMATORY-RELATED FACTORS MIGHT CONFER RISK OF DEVELOPING CRPS AFTER TRAUMATIC INJURY. VALIDATION FINDINGS DEMONSTRATE THE POTENTIAL OF USING ELECTRONIC HEALTH RECORDS LINKED TO DNA FOR GENOMIC STUDIES OF CRPS. 2019 19 5748 34 SOCIAL AND PHYSICAL ENVIRONMENTS EARLY IN DEVELOPMENT PREDICT DNA METHYLATION OF INFLAMMATORY GENES IN YOUNG ADULTHOOD. CHRONIC INFLAMMATION CONTRIBUTES TO A WIDE RANGE OF HUMAN DISEASES, AND ENVIRONMENTS IN INFANCY AND CHILDHOOD ARE IMPORTANT DETERMINANTS OF INFLAMMATORY PHENOTYPES. THE UNDERLYING BIOLOGICAL MECHANISMS CONNECTING EARLY ENVIRONMENTS WITH THE REGULATION OF INFLAMMATION IN ADULTHOOD ARE NOT KNOWN, BUT EPIGENETIC PROCESSES ARE PLAUSIBLE CANDIDATES. WE TESTED THE HYPOTHESIS THAT PATTERNS OF DNA METHYLATION (DNAM) IN INFLAMMATORY GENES IN YOUNG ADULTHOOD WOULD BE PREDICTED BY EARLY LIFE NUTRITIONAL, MICROBIAL, AND PSYCHOSOCIAL EXPOSURES PREVIOUSLY ASSOCIATED WITH LEVELS OF INFLAMMATION. DATA COME FROM A POPULATION-BASED LONGITUDINAL BIRTH COHORT STUDY IN METROPOLITAN CEBU, THE PHILIPPINES, AND DNAM WAS CHARACTERIZED IN WHOLE BLOOD SAMPLES FROM 494 PARTICIPANTS (AGE 20-22 Y). ANALYSES FOCUSED ON PROBES IN 114 TARGET GENES INVOLVED IN THE REGULATION OF INFLAMMATION, AND WE IDENTIFIED 10 SITES ACROSS NINE GENES WHERE THE LEVEL OF DNAM WAS SIGNIFICANTLY PREDICTED BY THE FOLLOWING VARIABLES: HOUSEHOLD SOCIOECONOMIC STATUS IN CHILDHOOD, EXTENDED ABSENCE OF A PARENT IN CHILDHOOD, EXPOSURE TO ANIMAL FECES IN INFANCY, BIRTH IN THE DRY SEASON, OR DURATION OF EXCLUSIVE BREASTFEEDING. TO EVALUATE THE BIOLOGICAL SIGNIFICANCE OF THESE SITES, WE TESTED FOR ASSOCIATIONS WITH A PANEL OF INFLAMMATORY BIOMARKERS MEASURED IN PLASMA OBTAINED AT THE SAME AGE AS DNAM ASSESSMENT. THREE SITES PREDICTED ELEVATED INFLAMMATION, AND ONE SITE PREDICTED LOWER INFLAMMATION, CONSISTENT WITH THE INTERPRETATION THAT LEVELS OF DNAM AT THESE SITES ARE FUNCTIONALLY RELEVANT. THIS PATTERN OF RESULTS POINTS TOWARD DNAM AS A POTENTIALLY IMPORTANT BIOLOGICAL MECHANISM THROUGH WHICH DEVELOPMENTAL ENVIRONMENTS SHAPE INFLAMMATORY PHENOTYPES ACROSS THE LIFE COURSE. 2017 20 1497 35 DNA METHYLATION AGE IS ACCELERATED IN ALCOHOL DEPENDENCE. ALCOHOL DEPENDENCE (ALC) IS A CHRONIC, RELAPSING DISORDER THAT INCREASES THE BURDEN OF CHRONIC DISEASE AND SIGNIFICANTLY CONTRIBUTES TO NUMEROUS PREMATURE DEATHS EACH YEAR. PREVIOUS RESEARCH SUGGESTS THAT CHRONIC, HEAVY ALCOHOL CONSUMPTION IS ASSOCIATED WITH DIFFERENTIAL DNA METHYLATION PATTERNS. IN ADDITION, DNA METHYLATION LEVELS AT CERTAIN CPG SITES HAVE BEEN CORRELATED WITH AGE. WE USED AN EPIGENETIC CLOCK TO INVESTIGATE THE POTENTIAL ROLE OF EXCESSIVE ALCOHOL CONSUMPTION IN EPIGENETIC AGING. WE EXPLORED THIS QUESTION IN FIVE INDEPENDENT COHORTS, INCLUDING DNA METHYLATION DATA DERIVED FROM DATASETS FROM BLOOD (N = 129, N = 329), LIVER (N = 92, N = 49), AND POSTMORTEM PREFRONTAL CORTEX (N = 46). ONE BLOOD DATASET AND ONE LIVER TISSUE DATASET OF INDIVIDUALS WITH ALC EXHIBITED POSITIVE AGE ACCELERATION (P < 0.0001 AND P = 0.0069, RESPECTIVELY), WHEREAS THE OTHER BLOOD AND LIVER TISSUE DATASETS BOTH EXHIBITED TRENDS OF POSITIVE AGE ACCELERATION THAT WERE NOT SIGNIFICANT (P = 0.83 AND P = 0.57, RESPECTIVELY). PREFRONTAL CORTEX TISSUE EXHIBITED A TREND OF NEGATIVE AGE ACCELERATION (P = 0.19). THESE RESULTS SUGGEST THAT EXCESSIVE ALCOHOL CONSUMPTION MAY BE ASSOCIATED WITH EPIGENETIC AGING IN A TISSUE-SPECIFIC MANNER AND WARRANTS FURTHER INVESTIGATION USING MULTIPLE TISSUE SAMPLES FROM THE SAME INDIVIDUALS. 2018