1 5463 176 RESIDENTIAL PM(2.5) EXPOSURE AND THE NASAL METHYLOME IN CHILDREN. RATIONALE: PM(2.5-)INDUCED ADVERSE EFFECTS ON RESPIRATORY HEALTH MAY BE DRIVEN BY EPIGENETIC MODIFICATIONS IN AIRWAY CELLS. THE POTENTIAL IMPACT OF EXPOSURE DURATION ON EPIGENETIC ALTERATIONS IN THE AIRWAYS IS NOT YET KNOWN. OBJECTIVES: WE AIMED TO STUDY ASSOCIATIONS OF FINE PARTICULATE MATTER PM(2.5) EXPOSURE WITH DNA METHYLATION IN NASAL CELLS. METHODS: WE CONDUCTED NASAL EPIGENOME-WIDE ASSOCIATION ANALYSES WITHIN 503 CHILDREN FROM PROJECT VIVA (MEAN AGE 12.9 Y), AND EXAMINED VARIOUS EXPOSURE DURATIONS (1-DAY, 1-WEEK, 1-MONTH, 3-MONTHS AND 1-YEAR) PRIOR TO NASAL SAMPLING. WE USED RESIDENTIAL ADDRESSES TO ESTIMATE AVERAGE DAILY PM(2.5) AT 1 KM RESOLUTION. WE COLLECTED NASAL SWABS FROM THE ANTERIOR NARES AND MEASURED DNA METHYLATION (DNAM) USING THE ILLUMINA METHYLATIONEPIC BEADCHIP. WE TESTED 719,075 HIGH QUALITY AUTOSOMAL CPGS USING CPG-BY-CPG AND REGIONAL DNAM ANALYSES CONTROLLING FOR MULTIPLE COMPARISONS, AND ADJUSTED FOR MATERNAL EDUCATION, HOUSEHOLD SMOKERS, CHILD SEX, RACE/ETHNICITY, BMI Z-SCORE, AGE, SEASON AT SAMPLE COLLECTION AND CELL-TYPE HETEROGENEITY. WE FURTHER CORRECTED FOR BIAS AND GENOMIC INFLATION. WE TESTED FOR REPLICATION IN A COHORT FROM THE NETHERLANDS (PIAMA). RESULTS: IN ADJUSTED ANALYSES, WE FOUND 362 CPGS ASSOCIATED WITH 1-YEAR PM(2.5) (FDR < 0.05), 20 CPGS PASSING BONFERRONI CORRECTION (P < 7.0X10(-8)) AND 10 DIFFERENTIALLY METHYLATED REGIONS (DMRS). IN 445 PIAMA PARTICIPANTS (MEAN AGE 16.3 YEARS) 11 OF 203 AVAILABLE CPGS REPLICATED AT P < 0.05. WE OBSERVED DIFFERENTIAL DNAM AT/NEAR GENES IMPLICATED IN CELL CYCLE, IMMUNE AND INFLAMMATORY RESPONSES. THERE WERE NO CPGS OR REGIONS ASSOCIATED WITH PM(2.5) LEVELS AT 1-DAY, 1-WEEK, OR 1-MONTH PRIOR TO SAMPLE COLLECTION, ALTHOUGH 2 CPGS WERE ASSOCIATED WITH PAST 3-MONTH PM(2.5). CONCLUSION: WE OBSERVED WIDE-SPREAD DNAM VARIABILITY ASSOCIATED WITH AVERAGE PAST YEAR PM(2.5) EXPOSURE BUT WE DID NOT DETECT ASSOCIATIONS WITH SHORTER-TERM EXPOSURE. OUR RESULTS SUGGEST THAT NASAL DNAM MARKS REFLECT CHRONIC AIR POLLUTION EXPOSURE. 2021 2 3063 58 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 /= 30 YEARS) TYPE 2 DIABETES WITHOUT DIABETIC RETINOPATHY. BACKGROUND: THIS STUDY AIMED TO DETERMINE THE EPIGENETIC BIOMARKERS OF DIABETIC RETINOPATHY (DR) IN SUBJECTS WITH TYPE 2 DIABETES MELLITUS (T2DM). THIS RETROSPECTIVE STUDY IS BASED ON THE SHANGHAI XINJING COMMUNITY PREVENTION AND TREATMENT ADMINISTRATIVE SYSTEM OF CHRONIC DISEASES. THE SUBJECTS ENROLLED HEREIN WERE T2DM PATIENTS WHO HAD UNDERGONE LONG-TERM FOLLOW-UP EVALUATION IN THE SYSTEM. TWO CONSECUTIVE STUDIES WERE CONDUCTED. IN THE DISCOVERY COHORT, AMONG 19 SUBJECTS WHO HAD DEVELOPED DR WITH A DM DURATION < 3 YEARS AND 21 SUBJECTS WITHOUT DR > 30 YEARS AFTER BEING DIAGNOSED WITH DM, AN INFINIUM HUMAN METHYLATION 850 BEADCHIP WAS USED TO IDENTIFY DIFFERENTIAL METHYLATION REGIONS (DMRS) AND DIFFERENTIAL METHYLATION SITES (DMSS). THE FUNCTION OF THE GENES WAS ASSESSED THROUGH KEGG ENRICHMENT ANALYSIS, GENE ONTOLOGY (GO) ANALYSIS, AND PATHWAY NETWORK ANALYSIS. IN THE REPLICATION COHORT, 87 DR PATIENTS WITH A SHORT DM DURATION AND 89 PATIENTS WITHOUT DR OVER A DM DURATION > 20 YEARS WERE COMPARED TO ASSESS THE ASSOCIATION BETWEEN DMSS AND DR UPON PYROSEQUENCING. RESULTS: A TOTAL OF 34 DMRS WERE IDENTIFIED. GENES CONTAINING DMSS WITH THE TOP 5 HIGHEST BETA VALUE DIFFERENCES BETWEEN DR AND NON-DR PARTICIPANTS WERE LOCATED ON CHROMOSOME 1 AND WERE PRESENT IN THE S100A13 GENE, WHICH WAS ASSOCIATED WITH 71 GO TERMS. TWO S100A13 GENE SITES, I.E., CG02873163 AND CG11343894, DISPLAYED A GOOD CORRELATION WITH DR ON PYROSEQUENCING. CONCLUSIONS: DMSS IN THE S100A13 GENE MAY BE POTENTIAL BIOMARKERS OF DR. 2020 8 2351 42 EPIGENETIC REGULATION OF NEWBORNS' IMPRINTED GENES RELATED TO GESTATIONAL GROWTH: PATTERNING BY PARENTAL RACE/ETHNICITY AND MATERNAL SOCIOECONOMIC STATUS. BACKGROUND: CHILDREN BORN TO PARENTS WITH LOWER INCOME AND EDUCATION ARE AT RISK FOR OBESITY AND LATER-LIFE RISK OF COMMON CHRONIC DISEASES, AND EPIGENETICS HAS BEEN HYPOTHESISED TO LINK THESE ASSOCIATIONS. HOWEVER, EPIGENETIC TARGETS ARE UNKNOWN. WE FOCUS ON A CLUSTER OF WELL-CHARACTERISED GENOMICALLY IMPRINTED GENES BECAUSE THEIR MONOALLELIC EXPRESSION IS REGULATED BY DNA METHYLATION AT DIFFERENTIALLY METHYLATED REGIONS (DMRS), ARE CRITICAL IN FETAL GROWTH, AND DNA METHYLATION PATTERNS AT BIRTH HAVE BEEN ASSOCIATED WITH INCREASED RISK OF BIRTH WEIGHT EXTREMES AND OVERWEIGHT STATUS OR OBESITY IN EARLY CHILDHOOD. METHODS: WE MEASURED DNA METHYLATION AT DMRS REGULATING GENOMICALLY IMPRINTED DOMAINS (IGF2/H19, DLK1/MEG3, NNAT AND PLAGL1) USING UMBILICAL CORD BLOOD LEUCOCYTES FROM 619 INFANTS RECRUITED IN DURHAM, NORTH CAROLINA IN 2010-2011. WE EXAMINED DIFFERENCES IN DNA METHYLATION LEVELS BY RACE/ETHNICITY OF BOTH PARENTS, AND THE ROLE THAT MATERNAL SOCIOECONOMIC STATUS (SES) MAY PLAY IN THE ASSOCIATION BETWEEN RACE/ETHNIC EPIGENETIC DIFFERENCES. RESULTS: UNADJUSTED RACE/ETHNIC DIFFERENCES ONLY WERE EVIDENT FOR DMRS REGULATING MEG3 AND IGF2; RACE/ETHNIC DIFFERENCES PERSISTED IN IGF2/H19 AND NNAT AFTER ACCOUNTING FOR INCOME AND EDUCATION. CONCLUSIONS: RESULTS SUGGEST THAT PARENTAL FACTORS MAY NOT ONLY INFLUENCE DNA METHYLATION, BUT ALSO DO SO IN WAYS THAT VARY BY DMR. FINDINGS SUPPORT THE HYPOTHESIS THAT EPIGENETICS MAY LINK THE OBSERVED LOWER SES DURING THE PRENATAL PERIOD AND POOR OUTCOMES SUCH AS LOW BIRTH WEIGHT; LOWER BIRTH WEIGHT HAS PREVIOUSLY BEEN ASSOCIATED WITH ADULT-ONSET CHRONIC DISEASES AND CONDITIONS THAT INCLUDE CARDIOVASCULAR DISEASES, DIABETES, OBESITY AND SOME CANCERS. 2015 9 2628 30 EPIGENOME-WIDE ASSOCIATION STUDY OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE AND LUNG FUNCTION IN KOREANS. AIM: TO IDENTIFY DIFFERENTIALLY METHYLATED PROBES (DMPS) AND REGIONS (DMRS) IN RELATION TO CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) AND LUNG FUNCTION TRAITS. METHODS: WE PERFORMED AN EPIGENOME-WIDE ASSOCIATION STUDY OF COPD AND SPIROMETRIC PARAMETERS, INCLUDING FORCED EXPIRATORY VOLUME IN 1 S (FEV1), FORCED VITAL CAPACITY (FVC) AND FEV1/FVC, IN BLOOD DNA USING THE INFINIUM HUMANMETHYLATION450 (N = 100, A KOREAN COPD COHORT). RESULTS: WE FOUND ONE SIGNIFICANT DMP (CG03559389, DIP2C) AND 104 SIGNIFICANT DMRS AFTER MULTIPLE-TESTING CORRECTION. OF THESE, 34 DMRS MAPPED TO GENES DIFFERENTIAL EXPRESSED WITH RESPECT TO THE SAME TRAIT. FIVE OF THE GENES WERE ASSOCIATED WITH MORE THAN TWO TRAITS: CTU2, USP36, ZNF516, KLK10 AND CPT1B. CONCLUSION: WE IDENTIFIED NOVEL DIFFERENTIAL METHYLATION LOCI RELATED TO COPD AND LUNG FUNCTION IN BLOOD DNA IN KOREANS AND CONFIRMED PREVIOUS FINDINGS IN NON-ASIANS. EPIGENETIC MODIFICATION COULD CONTRIBUTE TO THE ETIOLOGY OF THESE PHENOTYPES. 2017 10 1586 37 DNA METHYLATION PROFILING IDENTIFIES EPIGENETIC DIFFERENCES BETWEEN EARLY VERSUS LATE STAGES OF DIABETIC CHRONIC KIDNEY DISEASE. BACKGROUND: WE INVESTIGATED A CROSS-SECTIONAL EPIGENOME-WIDE ASSOCIATION STUDY OF PATIENTS WITH EARLY AND LATE DIABETES-ASSOCIATED CHRONIC KIDNEY DISEASE (CKD) TO IDENTIFY POSSIBLE EPIGENETIC DIFFERENCES BETWEEN THE TWO GROUPS AS WELL AS CHANGES IN METHYLATION ACROSS ALL STAGES OF DIABETIC CKD. WE ALSO EVALUATED THE POTENTIAL OF USING A PANEL OF IDENTIFIED 5'-C-PHOSPHATE-G-3' (CPG) SITES FROM THIS COHORT TO PREDICT THE PROGRESSION OF DIABETIC CKD. METHODS: THIS CROSS-SECTIONAL STUDY RECRUITED 119 ADULTS. DNA WAS EXTRACTED FROM BLOOD USING THE QIAGEN QIAAMPDNA MINI SPIN KIT. GENOME-WIDE METHYLATION ANALYSIS WAS PERFORMED USING ILLUMINA INFINIUM METHYLATIONEPIC BEADCHIPS (HM850K). INTENSITY DATA FILES WERE PROCESSED AND ANALYSED USING THE MINFI AND MISSMETHYL PACKAGES FOR R. WE EXAMINED THE DEGREE OF METHYLATION OF CPG SITES IN EARLY VERSUS LATE DIABETIC CKD PATIENTS FOR CPG SITES WITH AN UNADJUSTED P-VALUE <0.01 AND AN ABSOLUTE CHANGE IN METHYLATION OF 5% (N = 239 CPG SITES). RESULTS: HIERARCHICAL CLUSTERING OF THE 239 CPG SITES LARGELY SEPARATED THE TWO GROUPS. A HEAT MAP FOR ALL 239 CPG SITES DEMONSTRATED DISTINCT METHYLATION PATTERNS IN THE EARLY VERSUS LATE GROUPS, WITH CPG SITES SHOWING EVIDENCE OF PROGRESSIVE CHANGE. BASED ON OUR DIFFERENTIALLY METHYLATED REGION (DMR) ANALYSIS OF THE 239 CPG SITES, WE HIGHLIGHTED TWO DMRS, NAMELY THE CYSTEINE-RICH SECRETORY PROTEIN 2 (CRISP2) AND PIWI-LIKE RNA-MEDIATED GENE SILENCING 1 (PIWIL1) GENES. THE BEST PREDICTABILITY FOR THE TWO GROUPS INVOLVED A RECEIVER OPERATING CHARACTERISTICS CURVE OF EIGHT CPG SITES ALONE AND ACHIEVED AN AREA UNDER THE CURVE OF 0.976. CONCLUSIONS: WE HAVE IDENTIFIED DISTINCT DNA METHYLATION PATTERNS BETWEEN EARLY AND LATE DIABETIC CKD PATIENTS AS WELL AS DEMONSTRATED NOVEL FINDINGS OF POTENTIAL PROGRESSIVE METHYLATION CHANGES ACROSS ALL STAGES (1-5) OF DIABETIC CKD AT SPECIFIC CPG SITES. WE HAVE ALSO IDENTIFIED ASSOCIATED GENES CRISP2 AND PIWIL1, WHICH MAY HAVE THE POTENTIAL TO ACT AS STAGE-SPECIFIC DIABETES-ASSOCIATED CKD MARKERS, AND SHOWED THAT THE USE OF A PANEL OF EIGHT IDENTIFIED CPG SITES ALONE HELPS TO INCREASE THE PREDICTABILITY FOR THE TWO GROUPS. 2021 11 2903 37 GENDER-SPECIFIC METHYLATION DIFFERENCES IN RELATION TO PRENATAL EXPOSURE TO CIGARETTE SMOKE. EPIGENETIC ALTERATIONS MAY MECHANISTICALLY EXPLAIN THE DEVELOPMENTAL ORIGINS OF ADULT DISEASE, NAMELY THE HYPOTHESIS THAT MANY COMPLEX ADULT CHRONIC DISEASES ORIGINATE AS A RESULT OF CONDITIONS ENCOUNTERED IN UTERO. IF TRUE, EPIGENETICALLY REGULATED IMPRINTED GENES, CRITICAL TO NORMAL GROWTH AND DEVELOPMENT, MAY PARTIALLY MEDIATE THESE OUTCOMES. WE DETERMINED THE INFLUENCE OF IN UTERO EXPOSURE TO CIGARETTE SMOKING ON METHYLATION AT TWO DIFFERENTIALLY METHYLATED REGIONS (DMRS) REGULATING INSULIN-LIKE GROWTH FACTOR 2 (IGF2) AND H19, AND HOW THIS MIGHT RELATE TO BIRTH WEIGHT OF INFANTS BORN TO 418 PREGNANT WOMEN. SMOKING STATUS WAS ASCERTAINED THROUGH SELF-REPORT AND MEDICAL RECORDS. BISULFITE PYROSEQUENCING WAS USED TO MEASURE METHYLATION IN UMBILICAL CORD BLOOD DNAS. LEAST SQUARES DNA METHYLATION MEANS AT EACH DMR AND BIRTH WEIGHT WERE COMPARED BETWEEN INFANTS OF SMOKERS AND NON-SMOKERS, USING GENERALIZED LINEAR MODELS. WHILE THERE WERE NO SIGNIFICANT DIFFERENCES AT THE H19 DMR, INFANTS BORN TO SMOKERS HAD HIGHER METHYLATION AT THE IGF2 DMR THAN THOSE BORN TO NEVER SMOKERS OR THOSE WHO QUIT DURING PREGNANCY (49.5%, SD=8.0 VERSUS 46.6%, SD=5.6 AND 45.8%, SD=6.3, RESPECTIVELY; P=0.0002). THE SMOKING-RELATED INCREASE IN METHYLATION WAS MOST PRONOUNCED IN MALE OFFSPRING (P FOR SEX INTERACTION=0.03), FOR WHOM APPROXIMATELY 20% OF SMOKING-RELATED LOW BIRTH WEIGHT WAS MEDIATED BY DNA METHYLATION AT THE IGF2 DMR. OUR FINDINGS SUGGEST THAT IGF2 DMR PLASTICITY IS AN IMPORTANT MECHANISM BY WHICH IN UTERO ADJUSTMENTS TO ENVIRONMENTAL TOXICANTS ARE CONFERRED. LARGER STUDIES TO REPLICATE THESE FINDINGS ARE REQUIRED. 2012 12 3951 54 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 13 972 39 CHRONIC OBSTRUCTIVE PULMONARY DISEASE IS ASSOCIATED WITH EPIGENOME-WIDE DIFFERENTIAL METHYLATION IN BAL LUNG CELLS. DNA METHYLATION PATTERNS IN CHRONIC PULMONARY OBSTRUCTIVE DISEASE (COPD) MIGHT OFFER NEW INSIGHTS INTO DISEASE PATHOGENESIS. TO ASSESS METHYLATION PROFILES IN THE MAIN COPD TARGET ORGAN, WE PERFORMED AN EPIGENOME-WIDE ASSOCIATION STUDY ON BAL CELLS. BRONCHOSCOPIES WERE PERFORMED IN 18 SUBJECTS WITH COPD AND 15 CONTROL SUBJECTS (EX- AND CURRENT SMOKERS). DNA METHYLATION WAS MEASURED USING THE ILLUMINA METHYLATIONEPIC BEADCHIP KIT, COVERING MORE THAN 850,000 CPGS. DIFFERENTIALLY METHYLATED POSITIONS (DMPS) WERE EXAMINED FOR 1) ENRICHMENT IN PATHWAYS AND FUNCTIONAL GENE RELATIONSHIPS USING THE KYOTO ENCYCLOPEDIA OF GENES AND GENOMES AND GENE ONTOLOGY, 2) ACCELERATED AGING USING HORVATH'S EPIGENETIC CLOCK, 3) CORRELATION WITH GENE EXPRESSION, AND 4) COLOCALIZATION WITH GENETIC VARIATION. WE FOUND 1,155 BONFERRONI-SIGNIFICANT (P < 6.74 X 10(-8)) DMPS ASSOCIATED WITH COPD, MANY WITH LARGE EFFECT SIZES. FUNCTIONAL ANALYSIS IDENTIFIED BIOLOGICALLY PLAUSIBLE PATHWAYS AND GENE RELATIONSHIPS, INCLUDING ENRICHMENT FOR TRANSCRIPTION FACTOR ACTIVITY. STRONG CORRELATION WAS FOUND BETWEEN DNA METHYLATION AND CHRONOLOGICAL AGE BUT NOT BETWEEN COPD AND ACCELERATED AGING. FOR 79 UNIQUE DMPS, DNA METHYLATION CORRELATED SIGNIFICANTLY WITH GENE EXPRESSION IN BAL CELLS. THIRTY-NINE PERCENT OF DMPS WERE COLOCALIZED WITH COPD-ASSOCIATED SNPS. TO THE BEST OF OUR KNOWLEDGE, THIS IS THE FIRST EPIGENOME-WIDE ASSOCIATION STUDY OF COPD ON BAL CELLS, AND OUR ANALYSES REVEALED MANY DIFFERENTIAL METHYLATION SITES. INTEGRATION WITH MRNA DATA SHOWED A STRONG FUNCTIONAL READOUT FOR RELEVANT GENES, IDENTIFYING SITES WHERE DNA METHYLATION MIGHT DIRECTLY AFFECT EXPRESSION. ALMOST HALF OF DMPS WERE COLOCATED WITH SNPS IDENTIFIED IN PREVIOUS GENOME-WIDE ASSOCIATION STUDIES OF COPD, SUGGESTING JOINT GENETIC AND EPIGENETIC PATHWAYS RELATED TO DISEASE. 2022 14 1571 45 DNA METHYLATION PATTERNS IN CD8(+) T CELLS DISCERN PSORIASIS FROM PSORIATIC ARTHRITIS AND CORRELATE WITH CUTANEOUS DISEASE ACTIVITY. BACKGROUND: PSORIASIS IS A T CELL-MEDIATED CHRONIC AUTOIMMUNE/INFLAMMATORY DISEASE. WHILE SOME PATIENTS EXPERIENCE DISEASE LIMITED TO THE SKIN (SKIN PSORIASIS), OTHERS DEVELOP JOINT INVOLVEMENT (PSORIATIC ARTHRITIS; PSA). IN THE ABSENCE OF DISEASE- AND/OR OUTCOME-SPECIFIC BIOMARKERS, AND AS ARTHRITIS CAN PRECEDE SKIN MANIFESTATIONS, DIAGNOSTIC AND THERAPEUTIC DELAYS ARE COMMON AND CONTRIBUTE TO DISEASE BURDEN AND DAMAGE ACCRUAL. OBJECTIVE: ALTERED EPIGENETIC MARKS, INCLUDING DNA METHYLATION, CONTRIBUTE TO EFFECTOR T CELL PHENOTYPES AND ALTERED CYTOKINE EXPRESSION IN AUTOIMMUNE/INFLAMMATORY DISEASES. THIS PROJECT AIMED AT THE IDENTIFICATION OF DISEASE-/OUTCOME-SPECIFIC DNA METHYLATION SIGNATURES IN CD8(+) T CELLS FROM PATIENTS WITH PSORIASIS AND PSA AS COMPARED TO HEALTHY CONTROLS. METHOD: PERIPHERAL BLOOD CD8(+) T CELLS FROM NINE HEALTHY CONTROLS, 10 PSORIASIS, AND SEVEN PSA PATIENTS WERE COLLECTED TO ANALYZE DNA METHYLATION MARKS USING ILLUMINA HUMAN METHYLATION EPIC BEADCHIPS (>850,000 CPGS PER SAMPLE). BIOINFORMATIC ANALYSIS WAS PERFORMED USING R (MINFI, LIMMA, CHAMP, AND DMRCATE PACKAGES). RESULTS: DNA METHYLATION PROFILES IN CD8(+) T CELLS DIFFERENTIATE HEALTHY CONTROLS FROM PSORIASIS PATIENTS [397 DIFFERENTIALLY METHYLATED POSITIONS (DMPS); 9 DIFFERENTIALLY METHYLATED REGIONS (DMRS) WHEN >/=CPGS PER DMR WERE CONSIDERED; 2 DMRS FOR >/=10 CPGS]. FURTHERMORE, PATIENTS WITH SKIN PSORIASIS CAN BE DISCRIMINATED FROM PSA PATIENTS [1,861 DMPS, 20 DMRS (>/=5 CPGS PER REGION), 4 DMRS (>/=10 CPGS PER REGION)]. GENE ONTOLOGY (GO) ANALYSES CONSIDERING GENES WITH >/=1 DMP IN THEIR PROMOTER DELIVERED METHYLATION DEFECTS IN SKIN PSORIASIS AND PSA PRIMARILY AFFECTING THE BMP SIGNALING PATHWAY AND ENDOPEPTIDASE REGULATOR ACTIVITY, RESPECTIVELY. GO ANALYSIS OF GENES ASSOCIATED WITH DMRS BETWEEN SKIN PSORIASIS AND PSA DEMONSTRATED AN ENRICHMENT OF GABAERGIC NEURON AND CORTEX NEURON DEVELOPMENT PATHWAYS. TREATMENT WITH CYTOKINE BLOCKERS ASSOCIATED WITH DNA METHYLATION CHANGES [2,372 DMPS; 1,907 DMPS WITHIN PROMOTERS, 7 DMRS (>/=5 CPG PER REGIONS)] AFFECTING TRANSFORMING GROWTH FACTOR BETA RECEPTOR AND TRANSMEMBRANE RECEPTOR PROTEIN SERINE/THREONINE KINASE SIGNALING PATHWAYS. LASTLY, A METHYLATION SCORE INCLUDING TNF AND IL-17 PATHWAY ASSOCIATED DMPS INVERSE CORRELATES WITH SKIN DISEASE ACTIVITY SCORES (PASI). CONCLUSION: PATIENTS WITH SKIN PSORIASIS EXHIBIT DNA METHYLATION PATTERNS IN CD8(+) T CELLS THAT ALLOW DIFFERENTIATION FROM PSA PATIENTS AND HEALTHY INDIVIDUALS, AND REFLECT CLINICAL ACTIVITY OF SKIN DISEASE. THUS, DNA METHYLATION PROFILING PROMISES POTENTIAL AS DIAGNOSTIC AND PROGNOSTIC TOOL TO BE USED FOR MOLECULAR PATIENT STRATIFICATION TOWARD INDIVIDUALIZED TREATMENT. 2021 15 1521 44 DNA METHYLATION AT IMPRINT REGULATORY REGIONS IN PRETERM BIRTH AND INFECTION. OBJECTIVE: TO AID IN UNDERSTANDING LONG-TERM HEALTH CONSEQUENCES OF INTRAUTERINE INFECTIONS IN PRETERM BIRTH, WE EVALUATED DNA METHYLATION AT 9 DIFFERENTIALLY METHYLATED REGIONS THAT REGULATE IMPRINTED GENES BY TYPE OF PRETERM BIRTH (SPONTANEOUS PRETERM LABOR, PRETERM PREMATURE RUPTURE OF MEMBRANES, OR MEDICALLY INDICATED [FETAL GROWTH RESTRICTION AND PREECLAMPSIA]) AND INFECTION STATUS (CHORIOAMNIONITIS OR FUNISITIS). STUDY DESIGN: DATA ON TYPE OF PRETERM BIRTH AND INFECTION STATUS WERE ABSTRACTED FROM MEDICAL RECORDS AND STANDARDIZED PATHOLOGY REPORTS IN 73 PRETERM INFANTS ENROLLED IN THE NEWBORN EPIGENETICS STUDY, A PROSPECTIVE COHORT STUDY OF MOTHER-INFANT DYADS IN DURHAM, NC. CORD BLOOD WAS COLLECTED AT BIRTH, AND INFANT DNA METHYLATION LEVELS AT THE H19, IGF2, MEG3, MEST, SGCE/PEG10, PEG3, NNAT, AND PLAGL1 DIFFERENTIALLY METHYLATED REGIONS WERE MEASURED USING BISULFITE PYROSEQUENCING. ONE-WAY ANALYSES OF VARIANCE AND LOGISTIC REGRESSION MODELS WERE USED TO COMPARE DNA METHYLATION LEVELS BY TYPE OF PRETERM BIRTH AND INFECTION STATUS. RESULTS: DNA METHYLATION LEVELS DID NOT DIFFER AT ANY OF THE REGIONS (P > .20) BETWEEN INFANTS BORN VIA SPONTANEOUS PRETERM LABOR (AVERAGE N = 29), PRETERM PREMATURE RUPTURE OF MEMBRANES (AVERAGE N = 17), OR MEDICALLY INDICATED PRETERM BIRTH (AVERAGE N = 40). LEVELS WERE SIGNIFICANTLY INCREASED AT PLAGL1 IN INFANTS WITH CHORIOAMNIONITIS (N = 10, 64.4%) COMPARED WITH INFANTS WITHOUT CHORIOAMNIONITIS (N = 63, 57.9%), P < .01. DNA METHYLATION LEVELS WERE ALSO INCREASED AT PLAGL1 FOR INFANTS WITH FUNISITIS (N = 7, 63.3%) COMPARED WITH INFANTS WITHOUT FUNISITIS (N = 66, 58.3%), P < .05. CONCLUSION: DYSREGULATION OF PLAGL1 HAS BEEN ASSOCIATED WITH ABNORMAL DEVELOPMENT AND CANCER. EARLY-LIFE EXPOSURES, INCLUDING INFECTION/INFLAMMATION, MAY AFFECT EPIGENETIC CHANGES THAT INCREASE SUSCEPTIBILITY TO LATER CHRONIC DISEASE. 2013 16 308 40 ALCOHOL AND DNA METHYLATION: AN EPIGENOME-WIDE ASSOCIATION STUDY IN BLOOD AND NORMAL BREAST TISSUE. THE BIOLOGICAL MECHANISMS DRIVING ASSOCIATIONS BETWEEN ALCOHOL CONSUMPTION AND CHRONIC DISEASES MIGHT INCLUDE EPIGENETIC MODIFICATION OF DNA METHYLATION. WE EXPLORED THE HYPOTHESIS THAT ALCOHOL CONSUMPTION IS ASSOCIATED WITH METHYLATION IN AN EPIGENOME-WIDE ASSOCIATION STUDY OF BLOOD AND NORMAL BREAST TISSUE DNA. INFINIUM HUMANMETHYLATION450 BEADCHIP (ILLUMINA INC., SAN DIEGO, CALIFORNIA) ARRAY DATA ON BLOOD DNA METHYLATION WAS EXAMINED IN A DISCOVERY SET OF 2,878 NON-HISPANIC WHITE WOMEN FROM THE SISTER STUDY (UNITED STATES, 2004-2015) WHO PROVIDED DETAILED QUESTIONNAIRE INFORMATION ON LIFETIME ALCOHOL USE. ROBUST LINEAR REGRESSION MODELING WAS USED TO IDENTIFY SIGNIFICANT ASSOCIATIONS (FALSE DISCOVERY RATE OF Q < 0.05) BETWEEN THE NUMBER OF ALCOHOLIC DRINKS PER WEEK AND DNA METHYLATION AT 5,458 CYTOSINE-PHOSPHATE-GUANINE (CPG) SITES. ASSOCIATIONS WERE REPLICATED (P < 0.05) FOR 677 CPGS IN AN INDEPENDENT SET OF 187 BLOOD DNA SAMPLES FROM THE SISTER STUDY AND FOR 628 CPGS IN AN INDEPENDENT SET OF 171 NORMAL BREAST DNA SAMPLES; 1,207 CPGS WERE REPLICATED IN EITHER BLOOD OR NORMAL BREAST, WITH 98 CPGS REPLICATED IN BOTH TISSUES. INDIVIDUAL GENE EFFECTS WERE NOTABLE FOR PHOSPHOGLYCERATE DEHYDROGENASE (PGHDH), PEPTIDYL-PROLYL CIS-TRANS ISOMERASE (PPIF), SOLUTE CARRIER 15 (SLC15), SOLUTE CARRIER FAMILY 43 MEMBER 1 (SLC43A1), AND SOLUTE CARRIER FAMILY 7 MEMBER 11 (SLC7A11). WE ALSO FOUND THAT HIGH ALCOHOL CONSUMPTION WAS ASSOCIATED WITH SIGNIFICANTLY LOWER GLOBAL METHYLATION AS MEASURED BY THE AVERAGE OF CPGS ON THE ENTIRE ARRAY. 2019 17 521 49 ASSOCIATIONS BETWEEN MATERNAL PSYCHOSOCIAL STRESS, DNA METHYLATION, AND NEWBORN BIRTH WEIGHT IDENTIFIED BY INVESTIGATING METHYLATION AT INDIVIDUAL, REGIONAL, AND GENOME LEVELS. STRESS IS KNOWN TO AFFECT HEALTH THROUGHOUT LIFE AND INTO FUTURE GENERATIONS, BUT THE UNDERLYING MOLECULAR MECHANISMS ARE UNKNOWN. WE TESTED THE HYPOTHESIS THAT MATERNAL PSYCHOSOCIAL STRESS INFLUENCES DNA METHYLATION (DNAM), WHICH IN TURN IMPACTS NEWBORN HEALTH OUTCOMES. SPECIFICALLY, WE ANALYZED DNAM AT INDIVIDUAL, REGIONAL, AND GENOME-WIDE LEVELS TO TEST FOR ASSOCIATIONS WITH MATERNAL STRESS AND NEWBORN BIRTH WEIGHT. MATERNAL VENOUS BLOOD AND NEWBORN CORD BLOOD (N = 24 AND 22, RESPECTIVELY) WERE ASSAYED FOR METHYLATION AT APPROXIMATELY 450,000 CPG SITES. METHYLATION WAS ANALYZED BY EXAMINING CPG SITES INDIVIDUALLY IN AN EPIGENOME-WIDE ASSOCIATION STUDY (EWAS), AS REGIONAL GROUPS USING VARIABLY METHYLATED REGION (VMR) ANALYSIS IN MATERNAL BLOOD ONLY, AND THROUGH THE EPIGENOME-WIDE MEASURES USING GENOME-WIDE MEAN METHYLATION (GMM), HORVATH'S EPIGENETIC CLOCK, AND MITOTIC AGE. THESE METHYLATION MEASURES WERE TESTED FOR ASSOCIATION WITH THREE MEASURES OF MATERNAL STRESS (MATERNAL WAR TRAUMA, CHRONIC STRESS, AND EXPERIENCE OF SEXUAL VIOLENCE) AND ONE HEALTH OUTCOME (NEWBORN BIRTH WEIGHT). WE OBSERVED THAT MATERNAL EXPERIENCES OF WAR TRAUMA, CHRONIC STRESS, AND SEXUAL ASSAULT WERE EACH ASSOCIATED WITH DECREASED NEWBORN BIRTH WEIGHT (P < 1.95 X 10(-7) IN ALL CASES). TESTING INDIVIDUAL CPG SITES USING EWAS, WE OBSERVED NO ASSOCIATIONS BETWEEN DNAM AND ANY MEASURE OF MATERNAL STRESS OR NEWBORN BIRTH WEIGHT IN EITHER MATERNAL OR CORD BLOOD, AFTER BONFERRONI MULTIPLE TESTING CORRECTION. HOWEVER, THE TOP-RANKED CPG SITE IN MATERNAL BLOOD THAT ASSOCIATED WITH MATERNAL CHRONIC STRESS AND SEXUAL VIOLENCE BEFORE MULTIPLE TESTING CORRECTION IS LOCATED NEAR THE SPON1 GENE. TESTING AT A REGIONAL LEVEL, WE FOUND INCREASED METHYLATION OF A VMR IN MATERNAL BLOOD NEAR SPON1 THAT WAS ASSOCIATED WITH CHRONIC STRESS AND SEXUAL VIOLENCE AFTER BONFERRONI MULTIPLE TESTING CORRECTION (P = 1.95 X 10(-7) AND 8.3 X 10(-6), RESPECTIVELY). AT THE EPIGENOMIC LEVEL, CORD BLOOD GMM WAS ASSOCIATED WITH SIGNIFICANTLY HIGHER LEVELS OF WAR TRAUMA (P = 0.025) AND WAS SUGGESTIVELY ASSOCIATED WITH SEXUAL VIOLENCE (P = 0.053). THE OTHER TWO EPIGENOME-WIDE MEASURES WERE NOT ASSOCIATED WITH MATERNAL STRESS OR NEWBORN BIRTH WEIGHT IN EITHER TISSUE TYPE. DESPITE OUR SMALL SAMPLE SIZE, WE IDENTIFIED ASSOCIATIONS EVEN AFTER CONSERVATIVE MULTIPLE TESTING CORRECTION. SPECIFICALLY, WE FOUND ASSOCIATIONS BETWEEN DNAM AND THE THREE MEASURES OF MATERNAL STRESS ACROSS BOTH TISSUES; SPECIFICALLY, A VMR IN MATERNAL BLOOD AND GMM IN CORD BLOOD WERE BOTH ASSOCIATED WITH DIFFERENT MEASURES OF MATERNAL STRESS. THE ASSOCIATION OF CORD BLOOD GMM, BUT NOT MATERNAL BLOOD GMM, WITH MATERNAL STRESS MAY SUGGEST DIFFERENT RESPONSES TO STRESS IN MOTHER AND NEWBORN. IT IS NOTEWORTHY THAT WE FOUND ASSOCIATIONS ONLY WHEN CPG SITES WERE ANALYZED IN AGGREGATE, EITHER AS VMRS OR AS A BROAD SUMMARY MEASURE OF GMM. 2019 18 3056 41 GENOME-WIDE DNA METHYLATION ANALYSIS IMPLICATES ENRICHMENT OF INTERFERON PATHWAY IN AFRICAN AMERICAN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS AND EUROPEAN AMERICANS WITH LUPUS NEPHRITIS. SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) IS A CHRONIC, MULTISYSTEM, INFLAMMATORY AUTOIMMUNE DISEASE THAT DISPROPORTIONATELY AFFECTS WOMEN. TRENDS IN SLE PREVALENCE AND CLINICAL COURSE DIFFER BY ANCESTRY, WITH THOSE OF AFRICAN AMERICAN ANCESTRY PRESENTING WITH MORE ACTIVE, SEVERE AND RAPIDLY PROGRESSIVE DISEASE THAN EUROPEAN AMERICANS. PREVIOUS RESEARCH ESTABLISHED ALTERED EPIGENETIC SIGNATURES IN SLE PATIENTS COMPARED TO CONTROLS. HOWEVER, THE CONTRIBUTION OF ABERRANT DNA METHYLATION (DNAM) TO THE RISK OF SLE BY ANCESTRY AND DIFFERENCES AMONG PATIENTS WITH SLE-ASSOCIATED LUPUS NEPHRITIS (LN) HAS NOT BEEN WELL DESCRIBED. WE EVALUATED THE DNA METHYLOMES OF 87 INDIVIDUALS INCLUDING 41 SLE PATIENTS, WITH AND WITHOUT LN, AND 46 CONTROLS ENROLLED IN AN ANCESTRY DIVERSE, WELL-CHARACTERIZED COHORT STUDY OF ESTABLISHED SLE (41 SLE PATIENTS [20 SLE-LN+, 21 SLE-LN-] AND 46 SEX-, RACE- AND AGE-MATCHED CONTROLS; 55% AFRICAN AMERICAN, 45% EUROPEAN AMERICAN). PARTICIPANTS WERE GENOTYPED USING THE INFINIUM GLOBAL DIVERSITY ARRAY (GDA), AND GENETIC ANCESTRY WAS ESTIMATED USING PRINCIPAL COMPONENTS. GENOME-WIDE DNA METHYLATION WAS INITIALLY MEASURED USING THE ILLUMINA METHYLATIONEPIC 850K BEADCHIP ARRAY FOLLOWED BY METHYLATION-SPECIFIC QPCR TO VALIDATE THE METHYLATION STATUS AT PUTATIVE LOCI. DIFFERENTIALLY METHYLATED POSITIONS (DMP) WERE IDENTIFIED USING A CASE-CONTROL APPROACH ADJUSTED FOR ANCESTRY. WE IDENTIFIED A TOTAL OF 51 DMPS IN CPGS AMONG SLE PATIENTS COMPARED TO CONTROLS. GENES PROXIMAL TO THESE CPGS WERE HIGHLY ENRICHED FOR INVOLVEMENT IN TYPE I INTERFERON SIGNALING. DMPS AMONG EUROPEAN AMERICAN SLE PATIENTS WITH LN WERE SIMILAR TO AFRICAN AMERICAN SLE PATIENTS WITH AND WITHOUT LN. OUR FINDINGS WERE VALIDATED USING AN ORTHOGONAL, METHYL-SPECIFIC PCR FOR THREE SLE-ASSOCIATED DMPS NEAR OR PROXIMAL TO MX1, USP18, AND IFITM1. OUR STUDY CONFIRMS PREVIOUS REPORTS THAT DMPS IN CPGS ASSOCIATED WITH SLE ARE ENRICHED IN TYPE I INTERFERON GENES. HOWEVER, WE SHOW THAT EUROPEAN AMERICAN SLE PATIENTS WITH LN HAVE SIMILAR DNAM PATTERNS TO AFRICAN AMERICAN SLE PATIENTS IRRESPECTIVE OF LN, SUGGESTING THAT ABERRANT DNAM ALTERS ACTIVITY OF TYPE I INTERFERON PATHWAY LEADING TO MORE SEVERE DISEASE INDEPENDENT OF ANCESTRY. 2023 19 382 49 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 20 2643 39 EPIGENOMIC ASSOCIATION ANALYSIS IDENTIFIES SMOKING-RELATED DNA METHYLATION SITES IN AFRICAN AMERICANS. CIGARETTE SMOKING IS AN ENVIRONMENTAL RISK FACTOR FOR MANY CHRONIC DISEASES, AND DISEASE RISK CAN OFTEN BE MANAGED BY SMOKING CONTROL. SMOKING CAN INDUCE CELLULAR AND MOLECULAR CHANGES, INCLUDING EPIGENETIC MODIFICATION, BUT THE SHORT- AND LONG-TERM EPIGENETIC MODIFICATIONS CAUSED BY CIGARETTE SMOKING AT THE GENE LEVEL HAVE NOT BEEN WELL UNDERSTOOD. RECENT STUDIES HAVE IDENTIFIED SMOKING-RELATED DNA METHYLATION (DNAM) SITES IN CAUCASIANS. TO DETERMINE WHETHER THE SAME DNAM SITES ASSOCIATE WITH SMOKING IN AFRICAN AMERICANS, AND TO IDENTIFY NOVEL SMOKING-RELATED DNAM SITES, WE CONDUCTED A METHYLOME-WIDE ASSOCIATION STUDY OF CIGARETTE SMOKING USING A DISCOVERY SAMPLE OF 972 AFRICAN AMERICANS, AND A REPLICATION SAMPLE OF 239 AFRICAN AMERICANS WITH TWO ARRAY-BASED METHODS. AMONG 15 DNAM SITES SIGNIFICANTLY ASSOCIATED WITH SMOKING AFTER CORRECTION FOR MULTIPLE TESTING IN OUR DISCOVERY SAMPLE, 5 DNAM SITES ARE REPLICATED IN AN INDEPENDENT COHORT, AND 14 SITES IN THE REPLICATION SAMPLE HAVE EFFECTS IN THE SAME DIRECTION AS IN THE DISCOVERY SAMPLE. THE TOP TWO SMOKING-RELATED DNAM SITES IN F2RL3 (FACTOR II RECEPTOR-LIKE 3) AND GPR15 (G-PROTEIN-COUPLED RECEPTOR 15) OBSERVED IN AFRICAN AMERICANS ARE CONSISTENT WITH PREVIOUS FINDINGS IN CAUCASIANS. THE ASSOCIATIONS BETWEEN THE REPLICATED DNAM SITES AND SMOKING REMAIN SIGNIFICANT AFTER ADJUSTING FOR GENETIC BACKGROUND. DESPITE THE DISTINCT GENETIC BACKGROUND BETWEEN AFRICAN AMERICANS AND CAUCASIANS, THE DNAM FROM THE TWO ETHNIC GROUPS SHARES COMMON ASSOCIATIONS WITH CIGARETTE SMOKING, WHICH SUGGESTS A COMMON MOLECULAR MECHANISM OF EPIGENETIC MODIFICATION INFLUENCED BY ENVIRONMENTAL EXPOSURE. 2013