1 3063 156 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 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 6 5463 58 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 7 475 55 ARSENIC EXPOSURE AND HUMAN BLOOD DNA METHYLATION AND HYDROXYMETHYLATION PROFILES IN TWO DIVERSE POPULATIONS FROM BANGLADESH AND SPAIN. BACKGROUND: ASSOCIATIONS OF ARSENIC (AS) WITH THE SUM OF 5-MC AND 5-HMC LEVELS HAVE BEEN REPORTED; HOWEVER, AS EXPOSURE-RELATED DIFFERENCES OF THE SEPARATED 5-MC AND 5-HMC MARKERS HAVE RARELY BEEN STUDIED. METHODS: IN THIS STUDY, WE EVALUATED THE ASSOCIATION OF ARSENIC EXPOSURE BIOMARKERS AND 5-MC AND 5-HMC IN 30 HEALTHY MEN (43-55 YEARS) FROM THE ARAGON WORKERS HEALTH STUDY (AWHS) (SPAIN) AND 31 HEALTHY MEN (31-50 YEARS) FROM THE FOLIC ACID AND CREATININE TRIAL (FACT) (BANGLADESH). WE CONDUCTED 5-MC AND 5-HMC PROFILING USING INFINIUM METHYLATIONEPIC ARRAYS, ON PAIRED STANDARD AND MODIFIED (OX-BS IN AWHS AND TAB IN FACT) BISULFITE CONVERTED BLOOD DNA SAMPLES. RESULTS: THE MEDIAN FOR THE SUM OF URINE INORGANIC AND METHYLATED AS SPECIES (SIGMAAS) (MUG/L) WAS 12.5 FOR AWHS AND 89.6 FOR FACT. THE MEDIAN OF BLOOD AS (MUG/L) WAS 8.8 FOR AWHS AND 10.2 FOR FACT. AT A STATISTICAL SIGNIFICANCE P-VALUE CUT-OFF OF 0.01, THE DIFFERENTIALLY METHYLATED (DMP) AND HYDROXYMETHYLATED (DHP) POSITIONS WERE MOSTLY LOCATED IN DIFFERENT GENOMIC SITES. SEVERAL DMPS AND DHPS WERE CONSISTENTLY FOUND IN AWHS AND FACT BOTH FOR URINE SIGMAAS AND BLOOD MODELS, BEING OF SPECIAL INTEREST THOSE ATTRIBUTED TO THE DIP2C GENE. THREE DMPS (ANNOTATED TO CLEC12A) FOR AWHS AND ONE DHP (ANNOTATED TO NPLOC4) FOR FACT REMAINED STATISTICALLY SIGNIFICANT AFTER FALSE DISCOVERY RATE (FDR) CORRECTION. PATHWAYS RELATED TO CHRONIC DISEASES INCLUDING CARDIOVASCULAR, CANCER AND NEUROLOGICAL WERE ENRICHED. CONCLUSIONS: WHILE WE IDENTIFIED COMMON 5-HMC AND 5-MC SIGNATURES IN TWO POPULATIONS EXPOSED TO VARYING LEVELS OF INORGANIC AS, DIFFERENCES IN AS-RELATED EPIGENETIC SITES ACROSS THE STUDY POPULATIONS MAY ADDITIONALLY REFLECT LOW AND HIGH AS-SPECIFIC ASSOCIATIONS. THIS WORK CONTRIBUTES A DEEPER UNDERSTANDING OF POTENTIAL EPIGENETIC DYSREGULATIONS OF AS. HOWEVER, FURTHER RESEARCH IS NEEDED TO CONFIRM BIOLOGICAL CONSEQUENCES ASSOCIATED WITH DIP2C EPIGENETIC REGULATION AND TO INVESTIGATE THE ROLE OF 5-HMC AND 5-MC SEPARATELY IN AS-INDUCED HEALTH DISORDERS AT DIFFERENT EXPOSURE LEVELS. 2022 8 502 58 ASSOCIATION OF ARSENIC EXPOSURE WITH WHOLE BLOOD DNA METHYLATION: AN EPIGENOME-WIDE STUDY OF BANGLADESHI ADULTS. BACKGROUND: ARSENIC EXPOSURE AFFECTS [FORMULA: SEE TEXT] PEOPLE WORLDWIDE, INCLUDING [FORMULA: SEE TEXT] IN BANGLADESH. ARSENIC EXPOSURE INCREASES THE RISK OF CANCER AND OTHER CHRONIC DISEASES, AND ONE POTENTIAL MECHANISM OF ARSENIC TOXICITY IS EPIGENETIC DYSREGULATION. OBJECTIVE: WE ASSESSED ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND GENOME-WIDE DNA METHYLATION MEASURED AT BASELINE AMONG 396 BANGLADESHI ADULTS PARTICIPATING IN THE HEALTH EFFECTS OF ARSENIC LONGITUDINAL STUDY (HEALS) WHO WERE EXPOSED BY DRINKING NATURALLY CONTAMINATED WELL WATER. METHODS: METHYLATION IN WHOLE BLOOD DNA WAS MEASURED AT [FORMULA: SEE TEXT] USING THE ILLUMINA INFINIUMMETHYLATIONEPIC (EPIC) ARRAY. TO ASSESS ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND CPG METHYLATION, WE USED LINEAR REGRESSION MODELS ADJUSTED FOR COVARIATES AND SURROGATE VARIABLES (SVS) (CAPTURING UNKNOWN TECHNICAL AND BIOLOGIC FACTORS). WE ATTEMPTED REPLICATION AND CONDUCTED A META-ANALYSIS USING AN INDEPENDENT DATASET OF [FORMULA: SEE TEXT] FROM 400 BANGLADESHI INDIVIDUALS WITH ARSENICAL SKIN LESIONS. RESULTS: WE IDENTIFIED 34 CPGS ASSOCIATED WITH [FORMULA: SEE TEXT] CREATININE-ADJUSTED URINARY ARSENIC [[FORMULA: SEE TEXT]]. SIXTEEN OF THESE CPGS ANNOTATED TO THE [FORMULA: SEE TEXT] ARRAY, AND 10 ASSOCIATIONS WERE REPLICATED ([FORMULA: SEE TEXT]). THE TOP TWO CPGS ANNOTATED UPSTREAM OF THE ABR GENE (CG01912040, CG10003262 ). ALL URINARY ARSENIC-ASSOCIATED CPGS WERE ALSO ASSOCIATED WITH ARSENIC CONCENTRATION MEASURED IN DRINKING WATER ([FORMULA: SEE TEXT]). META-ANALYSIS ([FORMULA: SEE TEXT] SAMPLES) IDENTIFIED 221 URINARY ARSENIC-ASSOCIATED CPGS ([FORMULA: SEE TEXT]). THE ARSENIC-ASSOCIATED CPGS FROM THE META-ANALYSIS WERE ENRICHED IN NON-CPG ISLANDS AND SHORES ([FORMULA: SEE TEXT]) AND DEPLETED IN PROMOTER REGIONS ([FORMULA: SEE TEXT]). AMONG THE ARSENIC-ASSOCIATED CPGS ([FORMULA: SEE TEXT]), WE OBSERVED SIGNIFICANT ENRICHMENT OF GENES ANNOTATING TO THE REACTIVE OXYGEN SPECIES PATHWAY, INFLAMMATORY RESPONSE, AND TUMOR NECROSIS FACTOR [FORMULA: SEE TEXT] ([FORMULA: SEE TEXT]) SIGNALING VIA NUCLEAR FACTOR KAPPA-B ([FORMULA: SEE TEXT]) HALLMARKS ([FORMULA: SEE TEXT]). CONCLUSIONS: THE NOVEL AND REPLICABLE ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND DNA METHYLATION AT SPECIFIC CPGS OBSERVED IN THIS WORK SUGGEST THAT EPIGENETIC ALTERATIONS SHOULD BE FURTHER INVESTIGATED AS POTENTIAL MEDIATORS IN ARSENIC TOXICITY AND AS BIOMARKERS OF EXPOSURE AND EFFECT IN EXPOSED POPULATIONS. HTTPS://DOI.ORG/10.1289/EHP3849. 2019 9 308 43 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 10 2564 39 EPIGENETICS INSIGHTS INTO CHRONIC PAIN: DNA HYPOMETHYLATION IN FIBROMYALGIA-A CONTROLLED PILOT-STUDY. TO EVALUATE CHANGES IN DNA METHYLATION PROFILES IN PATIENTS WITH FIBROMYALGIA (FM) COMPARED TO MATCHED HEALTHY CONTROLS (HCS). ALL INDIVIDUALS UNDERWENT FULL CLINICAL AND NEUROPHYSIOLOGICAL ASSESSMENT BY CORTICAL EXCITABILITY (CE) PARAMETERS MEASURED BY TRANSCRANIAL MAGNETIC STIMULATION. DNA FROM THE PERIPHERAL BLOOD OF PATIENTS WITH FM (N = 24) AND HC (N = 24) WERE ASSESSED USING THE ILLUMINA-HUMANMETHYLATION450 BEADCHIPS. WE IDENTIFIED 1610 DIFFERENTIALLY METHYLATED POSITIONS (DMPS) IN PATIENTS WITH FM DISPLAYING A NONRANDOM DISTRIBUTION IN REGIONS OF THE GENOME. SIXTY-NINE PERCENT OF DMP IN FM WERE HYPOMETHYLATED COMPARED TO HC. DIFFERENTIALLY METHYLATED POSITIONS WERE ENRICHED IN 5 GENOMIC REGIONS (1P34; 6P21; 10Q26; 17Q25; 19Q13). THE FUNCTIONAL CHARACTERIZATION OF 960 GENES RELATED TO DMPS REVEALED AN ENRICHMENT FOR MAPK SIGNALING PATHWAY (N = 18 GENES), REGULATION OF ACTIN CYTOSKELETON (N = 15 GENES), AND FOCAL ADHESION (N = 13 GENES). A GENE-GENE INTERACTION NETWORK ENRICHMENT ANALYSIS REVEALED THE PARTICIPATION OF DNA REPAIR PATHWAYS, MITOCHONDRIA-RELATED PROCESSES, AND SYNAPTIC SIGNALING. EVEN THOUGH DNA WAS EXTRACTED FROM PERIPHERAL BLOOD, THIS SET OF GENES WAS ENRICHED FOR DISORDERS SUCH AS SCHIZOPHRENIA, MOOD DISORDERS, BULIMIA, HYPERPHAGIA, AND OBESITY. REMARKABLY, THE HIERARCHICAL CLUSTERIZATION BASED ON THE METHYLATION LEVELS OF THE 1610 DMPS SHOWED AN ASSOCIATION WITH NEUROPHYSIOLOGICAL MEASUREMENTS OF CE IN FM AND HC. FIBROMYALGIA HAS A HYPOMETHYLATION DNA PATTERN, WHICH IS ENRICHED IN GENES IMPLICATED IN STRESS RESPONSE AND DNA REPAIR/FREE RADICAL CLEARANCE. THESE CHANGES OCCURRED PARALLEL TO CHANGES IN CE PARAMETERS. NEW EPIGENETIC INSIGHTS INTO THE PATHOPHYSIOLOGY OF FM MAY PROVIDE THE BASIS FOR THE DEVELOPMENT OF BIOMARKERS OF THIS DISORDER. 2017 11 972 38 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 12 4690 33 NEWBORN DNA-METHYLATION, CHILDHOOD LUNG FUNCTION, AND THE RISKS OF ASTHMA AND COPD ACROSS THE LIFE COURSE. RATIONALE: WE AIMED TO IDENTIFY DIFFERENTIALLY METHYLATED REGIONS (DMRS) IN CORD BLOOD DNA ASSOCIATED WITH CHILDHOOD LUNG FUNCTION, ASTHMA AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) ACROSS THE LIFE COURSE. METHODS: WE META-ANALYSED EPIGENOME-WIDE DATA OF 1688 CHILDREN FROM FIVE COHORTS TO IDENTIFY CORD BLOOD DMRS AND THEIR ANNOTATED GENES, IN RELATION TO FORCED EXPIRATORY VOLUME IN 1 S (FEV(1)), FEV(1)/FORCED VITAL CAPACITY (FVC) RATIO AND FORCED EXPIRATORY FLOW AT 75% OF FVC AT AGES 7-13 YEARS. IDENTIFIED DMRS WERE EXPLORED FOR ASSOCIATIONS WITH CHILDHOOD ASTHMA, ADULT LUNG FUNCTION AND COPD, GENE EXPRESSION AND INVOLVEMENT IN BIOLOGICAL PROCESSES. RESULTS: WE IDENTIFIED 59 DMRS ASSOCIATED WITH CHILDHOOD LUNG FUNCTION, OF WHICH 18 WERE ASSOCIATED WITH CHILDHOOD ASTHMA AND NINE WITH COPD IN ADULTHOOD. GENES ANNOTATED TO THE TOP 10 IDENTIFIED DMRS WERE HOXA5, PAOX, LINC00602, ABCA7, PER3, CLCA1, VENTX, NUDT12, PTPRN2 AND TCL1A. DIFFERENTIAL GENE EXPRESSION IN BLOOD WAS OBSERVED FOR 32 DMRS IN CHILDHOOD AND 18 IN ADULTHOOD. GENES RELATED WITH 16 IDENTIFIED DMRS WERE ASSOCIATED WITH RESPIRATORY DEVELOPMENTAL OR PATHOGENIC PATHWAYS. INTERPRETATION: OUR FINDINGS SUGGEST THAT THE EPIGENETIC STATUS OF THE NEWBORN AFFECTS RESPIRATORY HEALTH AND DISEASE ACROSS THE LIFE COURSE. 2019 13 383 56 AN EPIGENOME-WIDE STUDY OF DNA METHYLATION PROFILES AND LUNG FUNCTION AMONG AMERICAN INDIANS IN THE STRONG HEART STUDY. BACKGROUND: EPIGENETIC MODIFICATIONS, INCLUDING DNA METHYLATION (DNAM), ARE OFTEN RELATED TO ENVIRONMENTAL EXPOSURES, AND ARE INCREASINGLY RECOGNIZED AS KEY PROCESSES IN THE PATHOGENESIS OF CHRONIC LUNG DISEASE. AMERICAN INDIAN COMMUNITIES HAVE A HIGH BURDEN OF LUNG DISEASE COMPARED TO THE NATIONAL AVERAGE. THE OBJECTIVE OF THIS STUDY WAS TO INVESTIGATE THE ASSOCIATION OF DNAM AND LUNG FUNCTION IN THE STRONG HEART STUDY (SHS). WE CONDUCTED A CROSS-SECTIONAL STUDY OF AMERICAN INDIAN ADULTS, 45-74 YEARS OF AGE WHO PARTICIPATED IN THE SHS. DNAM WAS MEASURED USING THE ILLUMINA INFINIUM HUMAN METHYLATIONEPIC PLATFORM AT BASELINE (1989-1991). LUNG FUNCTION WAS MEASURED VIA SPIROMETRY, INCLUDING FORCED EXPIRATORY VOLUME IN 1 S (FEV1) AND FORCED VITAL CAPACITY (FVC), AT VISIT 2 (1993-1995). AIRFLOW LIMITATION WAS DEFINED AS FEV1 < 70% PREDICTED AND FEV1/FVC < 0.7, RESTRICTION WAS DEFINED AS FEV1/FVC > 0.7 AND FVC < 80% PREDICTED, AND NORMAL SPIROMETRY WAS DEFINED AS FEV1/FVC > 0.7, FEV1 > 70% PREDICTED, FVC > 80% PREDICTED. WE USED ELASTIC-NET MODELS TO SELECT RELEVANT CPGS FOR LUNG FUNCTION AND SPIROMETRY-DEFINED LUNG DISEASE. WE ALSO CONDUCTED BIOINFORMATIC ANALYSES TO EVALUATE THE BIOLOGICAL PLAUSIBILITY OF THE FINDINGS. RESULTS: AMONG 1677 PARTICIPANTS, 21.2% HAD SPIROMETRY-DEFINED AIRFLOW LIMITATION AND 13.6% HAD SPIROMETRY-DEFINED RESTRICTIVE PATTERN LUNG FUNCTION. ELASTIC-NET MODELS SELECTED 1118 DIFFERENTIALLY METHYLATED POSITIONS (DMPS) AS PREDICTORS OF AIRFLOW LIMITATION AND 1385 FOR RESTRICTIVE PATTERN LUNG FUNCTION. A TOTAL OF 12 DMPS OVERLAPPED BETWEEN AIRFLOW LIMITATION AND RESTRICTIVE PATTERN. EGFR, MAPK1 AND PRPF8 GENES WERE THE MOST CONNECTED NODES IN THE PROTEIN-PROTEIN INTERACTION NETWORK. MANY OF THE DMPS TARGETED GENES WITH BIOLOGICAL ROLES RELATED TO LUNG FUNCTION SUCH AS PROTEIN KINASES. CONCLUSION: WE FOUND MULTIPLE DIFFERENTIALLY METHYLATED CPG SITES ASSOCIATED WITH CHRONIC LUNG DISEASE. THESE SIGNALS COULD CONTRIBUTE TO BETTER UNDERSTAND MOLECULAR MECHANISMS INVOLVED IN LUNG DISEASE, AS ASSESSED SYSTEMICALLY, AS WELL AS TO IDENTIFY PATTERNS THAT COULD BE USEFUL FOR DIAGNOSTIC PURPOSES. FURTHER EXPERIMENTAL AND LONGITUDINAL STUDIES ARE NEEDED TO ASSESS WHETHER DNA METHYLATION HAS A CAUSAL ROLE IN LUNG DISEASE. 2022 14 4256 33 METHYLOMIC MARKERS OF PERSISTENT CHILDHOOD ASTHMA: A LONGITUDINAL STUDY OF ASTHMA-DISCORDANT MONOZYGOTIC TWINS. BACKGROUND: ASTHMA IS THE MOST COMMON CHRONIC INFLAMMATORY DISORDER IN CHILDREN. THE AETIOLOGY OF ASTHMA PATHOLOGY IS COMPLEX AND HIGHLY HETEROGENEOUS, INVOLVING THE INTERPLAY BETWEEN GENETIC AND ENVIRONMENTAL RISK FACTORS THAT IS HYPOTHESIZED TO INVOLVE EPIGENETIC PROCESSES. OUR AIM WAS TO EXPLORE WHETHER METHYLOMIC VARIATION IN EARLY CHILDHOOD IS ASSOCIATED WITH DISCORDANCE FOR ASTHMA SYMPTOMS WITHIN MONOZYGOTIC (MZ) TWIN PAIRS RECRUITED FROM THE ENVIRONMENTAL RISK (E-RISK) LONGITUDINAL TWIN STUDY. WE ALSO AIMED TO IDENTIFY DIFFERENCES IN DNA METHYLATION THAT ARE ASSOCIATED WITH ASTHMA THAT DEVELOPS IN CHILDHOOD AND PERSISTS INTO EARLY ADULTHOOD AS THESE MAY REPRESENT USEFUL PROGNOSTIC BIOMARKERS. RESULTS: WE EXAMINED GENOME-WIDE PATTERNS OF DNA METHYLATION IN BUCCAL CELL SAMPLES COLLECTED FROM 37 MZ TWIN PAIRS DISCORDANT FOR ASTHMA AT AGE 10. DNA METHYLATION AT INDIVIDUAL CPG SITES DEMONSTRATED SIGNIFICANT VARIABILITY WITHIN DISCORDANT MZ TWIN PAIRS WITH THE TOP-RANKED NOMINALLY SIGNIFICANT DIFFERENTIALLY METHYLATED POSITION (DMP) LOCATED IN THE HGSNAT GENE. WE STRATIFIED OUR ANALYSIS BY ASSESSING DNA METHYLATION DIFFERENCES IN A SUB-GROUP OF MZ TWIN PAIRS WHO REMAINED PERSISTENTLY DISCORDANT FOR ASTHMA AT AGE 18. THE TOP-RANKED NOMINALLY SIGNIFICANT DMP ASSOCIATED WITH PERSISTING ASTHMA IS LOCATED IN THE VICINITY OF THE HLX GENE, WHICH HAS BEEN PREVIOUSLY IMPLICATED IN CHILDHOOD ASTHMA. CONCLUSIONS: WE IDENTIFIED DNA METHYLATION DIFFERENCES ASSOCIATED WITH CHILDHOOD ASTHMA IN PERIPHERAL DNA SAMPLES FROM DISCORDANT MZ TWIN PAIRS. OUR DATA SUGGEST THAT DIFFERENCES IN DNA METHYLATION ASSOCIATED WITH CHILDHOOD ASTHMA WHICH PERSISTS INTO EARLY ADULTHOOD ARE DISTINCT FROM THOSE ASSOCIATED WITH ASTHMA WHICH REMITS. 2015 15 3046 44 GENOME-WIDE ANALYSIS OF DNA METHYLATION IDENTIFIES S100A13 AS AN EPIGENETIC BIOMARKER IN INDIVIDUALS WITH CHRONIC (>/= 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 16 382 57 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 17 2623 43 EPIGENOME-WIDE ASSOCIATION STUDIES OF THE FRACTIONAL EXHALED NITRIC OXIDE AND BRONCHODILATOR DRUG RESPONSE IN MODERATE-TO-SEVERE PEDIATRIC ASTHMA. ASTHMA IS THE MOST PREVALENT PEDIATRIC CHRONIC DISEASE. BRONCHODILATOR DRUG RESPONSE (BDR) AND FRACTIONAL EXHALED NITRIC OXIDE (FENO) ARE CLINICAL BIOMARKERS OF ASTHMA. ALTHOUGH DNA METHYLATION (DNAM) CONTRIBUTES TO ASTHMA PATHOGENESIS, THE INFLUENCE OF DNAM ON BDR AND FENO IS SCARCELY INVESTIGATED. THIS STUDY AIMS TO IDENTIFY DNAM MARKERS IN WHOLE BLOOD ASSOCIATED EITHER WITH BDR OR FENO IN PEDIATRIC ASTHMA. WE ANALYZED 121 SAMPLES FROM CHILDREN WITH MODERATE-TO-SEVERE ASTHMA. THE ASSOCIATION OF GENOME-WIDE DNAM WITH BDR AND FENO HAS BEEN ASSESSED USING REGRESSION MODELS, ADJUSTING FOR AGE, SEX, ANCESTRY, AND TISSUE HETEROGENEITY. CROSS-TISSUE VALIDATION WAS ASSESSED IN 50 NASAL SAMPLES. DIFFERENTIALLY METHYLATED REGIONS (DMRS) AND ENRICHMENT IN TRAITS AND BIOLOGICAL PATHWAYS WERE ASSESSED. A FALSE DISCOVERY RATE (FDR) < 0.1 AND A GENOME-WIDE SIGNIFICANCE THRESHOLD OF P < 9 X 10(-8) WERE USED TO CONTROL FOR FALSE-POSITIVE RESULTS. THE CPG CG12835256 (PLA2G12A) WAS GENOME-WIDE ASSOCIATED WITH FENO IN BLOOD SAMPLES (COEFFICIENT= -0.015, P = 2.53 X 10(-9)) AND NOMINALLY ASSOCIATED IN NASAL SAMPLES (COEFFICIENT = -0.015, P = 0.045). ADDITIONALLY, THREE CPGS WERE SUGGESTIVELY ASSOCIATED WITH BDR (FDR < 0.1). WE IDENTIFIED 12 AND FOUR DMRS ASSOCIATED WITH FENO AND BDR (FDR < 0.05), RESPECTIVELY. AN ENRICHMENT IN ALLERGIC AND INFLAMMATORY PROCESSES, SMOKING, AND AGING WAS OBSERVED. WE REPORTED NOVEL ASSOCIATIONS OF DNAM MARKERS ASSOCIATED WITH BDR AND FENO ENRICHED IN ASTHMA-RELATED PROCESSES. 2023 18 2422 38 EPIGENETIC SIGNATURES DISCRIMINATE PATIENTS WITH PRIMARY SCLEROSING CHOLANGITIS AND ULCERATIVE COLITIS FROM PATIENTS WITH ULCERATIVE COLITIS. BACKGROUND: PRIMARY SCLEROSING CHOLANGITIS (PSC) IS A CHRONIC INFLAMMATORY LIVER DISEASE AFFECTING THE INTRA- AND EXTRAHEPATIC BILE DUCTS, AND IS STRONGLY ASSOCIATED WITH ULCERATIVE COLITIS (UC). IN THIS STUDY, WE EXPLORED THE PERIPHERAL BLOOD DNA METHYLOME AND ITS IMMUNE CELL COMPOSITION IN PATIENTS WITH PSC-UC, UC, AND HEALTHY CONTROLS (HC) WITH THE AIM TO DEVELOP A PREDICTIVE ASSAY IN DISTINGUISHING PATIENTS WITH PSC-UC FROM THOSE WITH UC ALONE. METHODS: THE PERIPHERAL BLOOD DNA METHYLOME OF MALE PATIENTS WITH PSC AND CONCOMITANT UC, UC AND HCS WAS PROFILED USING THE ILLUMINA HUMANMETHYLATION INFINIUM EPIC BEADCHIP (850K) ARRAY. DIFFERENTIALLY METHYLATED CPG POSITION (DMP) AND REGION (DMR) ANALYSES WERE PERFORMED ALONGSIDE GRADIENT BOOSTING CLASSIFICATION ANALYSES TO DISCERN PSC-UC FROM UC PATIENTS. AS OBSERVED DIFFERENCES IN THE DNA METHYLOME COULD BE THE RESULT OF DIFFERENCES IN CELLULAR POPULATIONS, WE ADDITIONALLY EMPLOYED MASS CYTOMETRY (CYTOF) TO CHARACTERIZE THE IMMUNE CELL COMPOSITIONS. RESULTS: GENOME WIDE METHYLATION ANALYSIS DID NOT REVEAL LARGE DIFFERENCES BETWEEN PSC-UC AND UC PATIENTS NOR HCS. NONETHELESS, USING GRADIENT BOOSTING WE WERE CAPABLE OF DISCERNING PSC-UC FROM UC WITH AN AREA UNDER THE RECEIVER OPERATOR CURVE (AUROC) OF 0.80. FOUR CPG SITES ANNOTATED TO THE NINJ2 GENE WERE FOUND TO STRONGLY CONTRIBUTE TO THE PREDICTIVE PERFORMANCE. WHILE CYTOF ANALYSES CORROBORATED THE LARGELY SIMILAR BLOOD CELL COMPOSITION AMONG PATIENTS WITH PSC-UC, UC AND HC, A HIGHER ABUNDANCE OF MYELOID CELLS WAS OBSERVED IN UC COMPARED TO PSC-UC PATIENTS. CONCLUSION: DNA METHYLATION ENABLES DISCERNING PSC-UC FROM UC PATIENTS, WITH A POTENTIAL FOR BIOMARKER DEVELOPMENT. 2022 19 3557 47 IMPACT OF BMI AND WAIST CIRCUMFERENCE ON EPIGENOME-WIDE DNA METHYLATION AND IDENTIFICATION OF EPIGENETIC BIOMARKERS IN BLOOD: AN EWAS IN MULTI-ETHNIC ASIAN INDIVIDUALS. BACKGROUND: THE PREVALENCE OF OBESITY AND ITS RELATED CHRONIC DISEASES HAVE BEEN INCREASING ESPECIALLY IN ASIAN COUNTRIES. OBESITY-RELATED GENETIC VARIANTS HAVE BEEN IDENTIFIED, BUT THESE EXPLAIN LITTLE OF THE VARIATION IN BMI. RECENT STUDIES REPORTED ASSOCIATIONS BETWEEN DNA METHYLATION AND OBESITY, MOSTLY IN NON-ASIAN POPULATIONS. METHODS: WE PERFORMED AN EPIGENOME-WIDE ASSOCIATION STUDY (EWAS) ON GENERAL ADIPOSITY (BODY MASS INDEX, BMI) AND ABDOMINAL ADIPOSITY (WAIST CIRCUMFERENCE, WC) IN 409 MULTI-ETHNIC ASIAN INDIVIDUALS AND REPLICATED BMI AND WAIST-ASSOCIATED DNA METHYLATION CPGS IDENTIFIED IN OTHER POPULATIONS. THE CROSS-LAGGED PANEL MODEL AND MENDELIAN RANDOMIZATION WERE USED TO ASSESS THE TEMPORAL RELATIONSHIP BETWEEN METHYLATION AND BMI. THE TEMPORAL RELATIONSHIP BETWEEN THE IDENTIFIED CPGS AND INFLAMMATION AND METABOLIC MARKERS WAS ALSO EXAMINED. RESULTS: EWAS IDENTIFIED 116 DNA METHYLATION CPGS INDEPENDENTLY ASSOCIATED WITH BMI AND EIGHT INDEPENDENTLY ASSOCIATED WITH WC AT FALSE DISCOVERY RATE P(FDR) < 0.05 IN 409 ASIAN SAMPLES. WE REPLICATED 110 BMI-ASSOCIATED CPGS PREVIOUSLY REPORTED IN EUROPEANS AND IDENTIFIED SIX NOVEL BMI-ASSOCIATED CPGS AND TWO NOVEL WC-ASSOCIATED CPGS. WE OBSERVED HIGH CONSISTENCY IN ASSOCIATION DIRECTION OF EFFECT COMPARED TO STUDIES IN OTHER POPULATIONS. CAUSAL RELATIONSHIP ANALYSES INDICATED THAT BMI WAS MORE LIKELY TO BE THE CAUSE OF DNA METHYLATION ALTERATION, RATHER THAN THE CONSEQUENCE. THE CAUSAL ANALYSES USING BMI-ASSOCIATED METHYLATION RISK SCORE ALSO SUGGESTED THAT HIGHER LEVELS OF THE INFLAMMATION MARKER IL-6 WERE LIKELY THE CONSEQUENCE OF METHYLATION CHANGE. CONCLUSION: OUR STUDY PROVIDES EVIDENCE OF AN ASSOCIATION BETWEEN OBESITY AND DNA METHYLATION IN MULTI-ETHNIC ASIANS AND SUGGESTS THAT OBESITY CAN DRIVE METHYLATION CHANGE. THE RESULTS ALSO SUGGESTED POSSIBLE CAUSAL INFLUENCE THAT OBESITY-RELATED METHYLATION CHANGES MIGHT HAVE ON INFLAMMATION AND LIPOPROTEIN LEVELS. 2021 20 2643 47 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