1 2643 118 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 2 5744 29 SMOKING-INDUCED EXPRESSION OF THE GPR15 GENE INDICATES ITS POTENTIAL ROLE IN CHRONIC INFLAMMATORY PATHOLOGIES. DESPITE THE DESCRIBED CLEAR EPIGENETIC EFFECTS OF SMOKING, THE EFFECT OF SMOKING ON GENOME-WIDE GENE EXPRESSION IN THE BLOOD IS OBSCURE. WE THEREFORE STUDIED THE SMOKING-INDUCED CHANGES IN THE GENE-EXPRESSION PROFILE OF THE PERIPHERAL BLOOD. RNA WAS EXTRACTED FROM THE WHOLE BLOOD OF 48 INDIVIDUALS WITH A DETAILED SMOKING HISTORY (24 NEVER-SMOKERS, 16 SMOKERS, AND 8 EX-SMOKERS). GENE-EXPRESSION PROFILES WERE EVALUATED WITH RNA SEQUENCING, AND RESULTS WERE ANALYZED SEPARATELY IN 24 MEN AND 24 WOMEN. IN THE MALE SMOKERS, 13 GENES WERE STATISTICALLY SIGNIFICANTLY (FALSE-DISCOVERY RATE <0.1) DIFFERENTIALLY EXPRESSED; IN FEMALE SMOKERS, 5 GENES. ALTHOUGH MOST OF THE DIFFERENTIALLY EXPRESSED GENES WERE DIFFERENT BETWEEN THE MALE AND FEMALE SMOKERS, THE G-PROTEIN-COUPLED RECEPTOR 15 GENE (GPR15) WAS DIFFERENTIALLY EXPRESSED IN BOTH MALE AND FEMALE SMOKERS COMPARED WITH NEVER-SMOKERS. ANALYSIS OF GPR15 METHYLATION IDENTIFIED SIGNIFICANTLY GREATER HYPOMETHYLATION IN SMOKERS COMPARED WITH THAT IN NEVER-SMOKERS. GPR15 IS THE CHEMOATTRACTANT RECEPTOR THAT REGULATES T-CELL MIGRATION AND IMMUNITY. UP-REGULATION OF GPR15 COULD EXPLAIN TO SOME EXTENT THE HEALTH HAZARDS OF SMOKING WITH REGARD TO CHRONIC INFLAMMATORY DISEASES. 2015 3 6761 58 X CHROMOSOME-WIDE ANALYSIS IDENTIFIES DNA METHYLATION SITES INFLUENCED BY CIGARETTE SMOKING. BACKGROUND: TOBACCO SMOKING IS A MAJOR CAUSE OF CHRONIC DISEASE WORLDWIDE. SMOKING MAY INDUCE CELLULAR AND MOLECULAR CHANGES INCLUDING EPIGENETIC MODIFICATION, WITH BOTH SHORT-TERM AND LONG-TERM MODIFICATION PATTERNS THAT MAY CONTRIBUTE TO PHENOTYPIC EXPRESSION OF DISEASES. RECENT EPIGENOME-WIDE ASSOCIATION STUDIES (EWAS) HAVE IDENTIFIED DOZENS OF SMOKING-RELATED DNA METHYLATION (DNAM) SITES. HOWEVER, THE X CHROMOSOMAL DNAM SITES HAVE BEEN LARGELY OVERLOOKED DUE TO A LACK OF AN ANALYTICAL FRAMEWORK FOR DEALING WITH THE SEX-DIMORPHIC DISTRIBUTION. TO IDENTIFY NOVEL SMOKING-RELATED DNAM SITES ON THE X CHROMOSOME, WE EXAMINED THE MODALITY OF EACH X CHROMOSOMAL DNAM SITE AND CONDUCTED A SEX-SPECIFIC ASSOCIATION STUDY OF CIGARETTE SMOKING. RESULTS: WE USED A DISCOVERY SAMPLE OF 139 MIDDLE-AGE TWINS, AND THREE REPLICATION SAMPLES OF 78 TWINS, 464 AND 333 UNRELATED INDIVIDUALS INCLUDING 47, 17, 22, AND 89 CURRENT SMOKERS, RESPECTIVELY. AFTER CORRECTION FOR MULTIPLE TESTING, THE TOP SMOKING-RELATED DNAM SITES IN BCOR AND TSC22D3 WERE SIGNIFICANTLY HYPERMETHYLATED AND HYPOMETHYLATED, RESPECTIVELY, AMONG CURRENT SMOKERS. THESE SMOKING-ASSOCIATED SITES WERE REPLICATED WITH META-ANALYSIS P-VALUES OF 9.17 X 10(-12) AND 1.61 X 10(-9). FOR BOTH SITES, THE SMOKING EFFECTS ON METHYLATION LEVELS WERE LARGER IN MALES THAN THAT IN FEMALES. CONCLUSIONS: OUR FINDINGS HIGHLIGHT THE IMPORTANCE OF INVESTIGATING X CHROMOSOME METHYLATION PATTERNS AND THEIR ASSOCIATIONS WITH ENVIRONMENTAL EXPOSURES AND DISEASE PHENOTYPES AND DEMONSTRATE A ROBUST STATISTICAL METHODOLOGY FOR SUCH STUDY. EXISTING EWAS OF HUMAN DISEASES SHOULD INCORPORATE THE X CHROMOSOMAL SITES TO COMPLETE A COMPREHENSIVE EPIGENOME-WIDE SCAN. 2016 4 3079 47 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 5 5745 49 SMOKING-RELATED CHANGES IN DNA METHYLATION AND GENE EXPRESSION ARE ASSOCIATED WITH CARDIO-METABOLIC TRAITS. BACKGROUND: TOBACCO SMOKING IS A WELL-KNOWN MODIFIABLE RISK FACTOR FOR MANY CHRONIC DISEASES, INCLUDING CARDIOVASCULAR DISEASE (CVD). ONE OF THE PROPOSED UNDERLYING MECHANISM LINKING SMOKING TO DISEASE IS VIA EPIGENETIC MODIFICATIONS, WHICH COULD AFFECT THE EXPRESSION OF DISEASE-ASSOCIATED GENES. HERE, WE CONDUCTED A THREE-WAY ASSOCIATION STUDY TO IDENTIFY THE RELATIONSHIP BETWEEN SMOKING-RELATED CHANGES IN DNA METHYLATION AND GENE EXPRESSION AND THEIR ASSOCIATIONS WITH CARDIO-METABOLIC TRAITS. RESULTS: WE SELECTED 2549 CPG SITES AND 443 GENE EXPRESSION PROBES ASSOCIATED WITH CURRENT VERSUS NEVER SMOKERS, FROM THE LARGEST EPIGENOME-WIDE ASSOCIATION STUDY AND TRANSCRIPTOME-WIDE ASSOCIATION STUDY TO DATE. WE EXAMINED THREE-WAY ASSOCIATIONS, INCLUDING CPG VERSUS GENE EXPRESSION, CARDIO-METABOLIC TRAIT VERSUS CPG, AND CARDIO-METABOLIC TRAIT VERSUS GENE EXPRESSION, IN THE ROTTERDAM STUDY. SUBSEQUENTLY, WE REPLICATED OUR FINDINGS IN THE COOPERATIVE HEALTH RESEARCH IN THE REGION OF AUGSBURG (KORA) STUDY. AFTER CORRECTION FOR MULTIPLE TESTING, WE IDENTIFIED BOTH CIS- AND TRANS-EXPRESSION QUANTITATIVE TRAIT METHYLATION (EQTM) ASSOCIATIONS IN BLOOD. SPECIFICALLY, WE FOUND 1224 SMOKING-RELATED CPGS ASSOCIATED WITH AT LEAST ONE OF THE 443 GENE EXPRESSION PROBES, AND 200 SMOKING-RELATED GENE EXPRESSION PROBES TO BE ASSOCIATED WITH AT LEAST ONE OF THE 2549 CPGS. OUT OF THESE, 109 CPGS AND 27 GENES WERE ASSOCIATED WITH AT LEAST ONE CARDIO-METABOLIC TRAIT IN THE ROTTERDAM STUDY. WE WERE ABLE TO REPLICATE THE ASSOCIATIONS WITH CARDIO-METABOLIC TRAITS OF 26 CPGS AND 19 GENES IN THE KORA STUDY. FURTHERMORE, WE IDENTIFIED A THREE-WAY ASSOCIATION OF TRIGLYCERIDES WITH TWO CPGS AND TWO GENES (GZMA; CLDND1), AND BMI WITH SIX CPGS AND TWO GENES (PID1; LRRN3). FINALLY, OUR RESULTS REVEALED THE MEDIATION EFFECT OF CG03636183 (F2RL3), CG06096336 (PSMD1), CG13708645 (KDM2B), AND CG17287155 (AHRR) WITHIN THE ASSOCIATION BETWEEN SMOKING AND LRRN3 EXPRESSION. CONCLUSIONS: OUR STUDY INDICATES THAT SMOKING-RELATED CHANGES IN DNA METHYLATION AND GENE EXPRESSION ARE ASSOCIATED WITH CARDIO-METABOLIC RISK FACTORS. THESE FINDINGS MAY PROVIDE ADDITIONAL INSIGHTS INTO THE MOLECULAR MECHANISMS LINKING SMOKING TO THE DEVELOPMENT OF CVD. 2020 6 5746 35 SMOKING-RELATED DNA METHYLATION IS ASSOCIATED WITH DNA METHYLATION PHENOTYPIC AGE ACCELERATION: THE VETERANS AFFAIRS NORMATIVE AGING STUDY. DNA METHYLATION MAY PLAY A CRITICAL ROLE IN AGING AND AGE-RELATED DISEASES. DNA METHYLATION PHENOTYPIC AGE (DNAMPHENOAGE) IS A NEW AGING BIOMARKER AND PREDICTOR OF CHRONIC DISEASE RISK. WHILE SMOKING IS A STRONG RISK FACTOR FOR CHRONIC DISEASES AND INFLUENCES METHYLATION, ITS INFLUENCE ON DNAMPHENOAGE IS UNKNOWN. WE INVESTIGATED ASSOCIATIONS OF SELF-REPORTED AND EPIGENETIC SMOKING INDICATORS WITH DNAMPHENOAGE ACCELERATION IN A LONGITUDINAL AGING STUDY IN EASTERN MASSACHUSETTS. DNA METHYLATION WAS MEASURED IN WHOLE BLOOD SAMPLES FROM MULTIPLE VISITS FOR 692 MALE PARTICIPANTS IN THE VETERANS AFFAIRS NORMATIVE AGING STUDY DURING 1999-2013. ACCELERATION WAS DEFINED USING RESIDUALS FROM LINEAR REGRESSION OF THE DNAMPHENOAGE ON THE CHRONOLOGICAL AGE. CUMULATIVE SMOKING (PACK-YEARS) WAS SIGNIFICANTLY ASSOCIATED WITH DNAMPHENOAGE ACCELERATION, WHEREAS SELF-REPORTED SMOKING STATUS WAS NOT. WE OBSERVED SIGNIFICANT VALIDATED ASSOCIATIONS BETWEEN SMOKING-RELATED LOCI AND DNAMPHENOAGE ACCELERATION FOR 52 CPG SITES, WHERE 18 WERE HYPOMETHYLATED AND 34 WERE HYPERMETHYLATED, MAPPED TO 16 GENES. THE AHRR GENE HAD THE MOST LOCI (N = 8) AMONG THE 16 GENES. WE GENERATED A SMOKING AGING INDEX BASED ON THESE 52 LOCI, WHICH SHOWED POSITIVE SIGNIFICANT ASSOCIATIONS WITH DNAMPHENOAGE ACCELERATION. THESE EPIGENETIC BIOMARKERS MAY HELP TO PREDICT AGE-RELATED RISKS DRIVEN BY SMOKING. 2019 7 1552 41 DNA METHYLATION IS PREDICTIVE OF MORTALITY IN CURRENT AND FORMER SMOKERS. RATIONALE: SMOKING RESULTS IN AT LEAST A DECADE LOWER LIFE EXPECTANCY. MORTALITY AMONG CURRENT SMOKERS IS TWO TO THREE TIMES AS HIGH AS NEVER SMOKERS. DNA METHYLATION IS AN EPIGENETIC MODIFICATION OF THE HUMAN GENOME THAT HAS BEEN ASSOCIATED WITH BOTH CIGARETTE SMOKING AND MORTALITY.OBJECTIVES: WE SOUGHT TO IDENTIFY DNA METHYLATION MARKS IN BLOOD THAT ARE PREDICTIVE OF MORTALITY IN A SUBSET OF THE COPDGENE (GENETIC EPIDEMIOLOGY OF COPD) STUDY, REPRESENTING 101 DEATHS AMONG 667 CURRENT AND FORMER SMOKERS.METHODS: WE ASSAYED GENOME-WIDE DNA METHYLATION IN NON-HISPANIC WHITE SMOKERS WITH AND WITHOUT CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) USING BLOOD SAMPLES FROM THE COPDGENE ENROLLMENT VISIT. WE TESTED WHETHER DNA METHYLATION WAS ASSOCIATED WITH MORTALITY IN MODELS ADJUSTED FOR COPD STATUS, AGE, SEX, CURRENT SMOKING STATUS, AND PACK-YEARS OF CIGARETTE SMOKING. REPLICATION WAS PERFORMED IN A SUBSET OF 231 INDIVIDUALS FROM THE ECLIPSE (EVALUATION OF COPD LONGITUDINALLY TO IDENTIFY PREDICTIVE SURROGATE ENDPOINTS) STUDY.MEASUREMENTS AND MAIN RESULTS: WE IDENTIFIED SEVEN CPG SITES ASSOCIATED WITH MORTALITY (FALSE DISCOVERY RATE < 20%) THAT REPLICATED IN THE ECLIPSE COHORT (P < 0.05). NONE OF THESE MARKS WERE ASSOCIATED WITH LONGITUDINAL LUNG FUNCTION DECLINE IN SURVIVORS, SMOKING HISTORY, OR CURRENT SMOKING STATUS. HOWEVER, DIFFERENTIAL METHYLATION OF TWO REPLICATED PIK3CD (PHOSPHATIDYLINOSITOL-4,5-BISPHOSPHATE 3-KINASE CATALYTIC SUBUNIT DELTA) SITES WERE ASSOCIATED WITH LUNG FUNCTION AT ENROLLMENT (P < 0.05). WE ALSO OBSERVED ASSOCIATIONS BETWEEN DNA METHYLATION AND GENE EXPRESSION FOR THE PIK3CD SITES.CONCLUSIONS: THIS STUDY IS THE FIRST TO IDENTIFY VARIABLE DNA METHYLATION ASSOCIATED WITH ALL-CAUSE MORTALITY IN SMOKERS WITH AND WITHOUT COPD. EVALUATING PREDICTIVE EPIGENOMIC MARKS OF SMOKERS IN PERIPHERAL BLOOD MAY ALLOW FOR TARGETED RISK STRATIFICATION AND AID IN DELIVERY OF FUTURE TAILORED THERAPEUTIC INTERVENTIONS. 2020 8 972 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 9 2628 32 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 1705 43 DYNAMICS OF SMOKING-INDUCED GENOME-WIDE METHYLATION CHANGES WITH TIME SINCE SMOKING CESSATION. SEVERAL STUDIES HAVE RECENTLY IDENTIFIED STRONG EPIGENETIC SIGNALS RELATED TO TOBACCO SMOKING. HOWEVER, AN ASPECT THAT DID NOT RECEIVE MUCH ATTENTION IS THE EVOLUTION OF EPIGENETIC CHANGES WITH TIME SINCE SMOKING CESSATION. WE CONDUCTED A SERIES OF EPIGENOME-WIDE ASSOCIATION STUDIES TO CAPTURE THE DYNAMICS OF SMOKING-INDUCED EPIGENETIC CHANGES AFTER SMOKING CESSATION, USING GENOME-WIDE METHYLATION PROFILES OBTAINED FROM BLOOD SAMPLES IN 745 WOMEN FROM 2 EUROPEAN POPULATIONS. TWO DISTINCT CLASSES OF CPG SITES WERE IDENTIFIED: SITES WHOSE METHYLATION REVERTS TO LEVELS TYPICAL OF NEVER SMOKERS WITHIN DECADES AFTER SMOKING CESSATION, AND SITES REMAINING DIFFERENTIALLY METHYLATED, EVEN MORE THAN 35 YEARS AFTER SMOKING CESSATION. OUR RESULTS SUGGEST THAT THE DYNAMICS OF METHYLATION CHANGES FOLLOWING SMOKING CESSATION ARE DRIVEN BY A DIFFERENTIAL AND SITE-SPECIFIC MAGNITUDE OF THE SMOKING-INDUCED ALTERATIONS (WITH PERSISTENT SITES BEING MOST AFFECTED) IRRESPECTIVE OF THE INTENSITY AND DURATION OF SMOKING. ANALYSES OF THE LINK BETWEEN METHYLATION AND EXPRESSION LEVELS REVEALED THAT METHYLATION PREDOMINANTLY AND REMOTELY DOWN-REGULATES GENE EXPRESSION. AMONG GENES WHOSE EXPRESSION WAS ASSOCIATED WITH OUR CANDIDATE CPG SITES, LRRN3 APPEARED TO BE PARTICULARLY INTERESTING AS IT WAS ONE OF THE FEW GENES WHOSE METHYLATION AND EXPRESSION WERE DIRECTLY ASSOCIATED, AND THE ONLY GENE IN WHICH BOTH METHYLATION AND GENE EXPRESSION WERE FOUND ASSOCIATED WITH SMOKING. OUR STUDY HIGHLIGHTS PERSISTENT EPIGENETIC MARKERS OF SMOKING, WHICH CAN POTENTIALLY BE DETECTED DECADES AFTER CESSATION. SUCH HISTORICAL SIGNATURES ARE PROMISING BIOMARKERS TO REFINE INDIVIDUAL RISK PROFILING OF SMOKING-INDUCED CHRONIC DISEASE SUCH AS LUNG CANCER. 2015 11 6190 51 THE IMPACT OF METHYLATION QUANTITATIVE TRAIT LOCI (MQTLS) ON ACTIVE SMOKING-RELATED DNA METHYLATION CHANGES. BACKGROUND: METHYLATION QUANTITATIVE TRAIT LOCI (MQTLS) ARE THE GENETIC VARIANTS THAT MAY AFFECT THE DNA METHYLATION PATTERNS OF CPG SITES. HOWEVER, THEIR ROLES IN INFLUENCING THE DISTURBANCES OF SMOKING-RELATED EPIGENETIC CHANGES HAVE NOT BEEN WELL ESTABLISHED. THIS STUDY WAS CONDUCTED TO ADDRESS WHETHER MQTLS EXIST IN THE VICINITY OF SMOKING-RELATED CPG SITES (+/- 50 KB) AND TO EXAMINE THEIR ASSOCIATIONS WITH SMOKING EXPOSURE AND ALL-CAUSE MORTALITY IN OLDER ADULTS. RESULTS: WE OBTAINED DNA METHYLATION PROFILES IN WHOLE BLOOD SAMPLES BY ILLUMINA INFINIUM HUMAN METHYLATION 450 BEADCHIP ARRAY OF TWO INDEPENDENT SUBSAMPLES OF THE ESTHER STUDY (DISCOVERY SET, N = 581; VALIDATION SET, N = 368) AND THEIR CORRESPONDING GENOTYPING DATA USING THE ILLUMINA INFINIUM ONCOARRAY BEADCHIP. AFTER CORRECTION FOR MULTIPLE TESTING (FDR), WE SUCCESSFULLY IDENTIFIED THAT 70 OUT OF 151 PREVIOUSLY REPORTED SMOKING-RELATED CPG SITES WERE SIGNIFICANTLY ASSOCIATED WITH 192 SNPS WITHIN THE 50 KB SEARCH WINDOW OF EACH LOCUS. THE 192 MQTLS SIGNIFICANTLY INFLUENCED THE ACTIVE SMOKING-RELATED DNA METHYLATION CHANGES, WITH PERCENTAGE CHANGES RANGING FROM 0.01 TO 18.96%, ESPECIALLY FOR THE WEAKLY/MODERATELY SMOKING-RELATED CPG SITES. HOWEVER, THESE IDENTIFIED MQTLS WERE NOT DIRECTLY ASSOCIATED WITH ACTIVE SMOKING EXPOSURE OR ALL-CAUSE MORTALITY. CONCLUSIONS: OUR FINDINGS CLEARLY DEMONSTRATED THAT IF NOT DEALT WITH PROPERLY, THE MQTLS MIGHT IMPAIR THE POWER OF EPIGENETIC-BASED MODELS OF SMOKING EXPOSURE TO A CERTAIN EXTENT. IN ADDITION, SUCH GENETIC VARIANTS COULD BE THE KEY FACTOR TO DISTINGUISH BETWEEN THE HERITABLE AND SMOKING-INDUCED IMPACT ON EPIGENOME DISPARITIES. THESE MQTLS ARE OF SPECIAL IMPORTANCE WHEN DNA METHYLATION MARKERS MEASURED BY ILLUMINA INFINIUM ASSAY ARE USED FOR ANY COMPARATIVE POPULATION STUDIES RELATED TO SMOKING-RELATED CANCERS AND CHRONIC DISEASES. 2017 12 304 38 AIRWAY AGING AND METHYLATION DISRUPTIONS IN HIV-ASSOCIATED CHRONIC OBSTRUCTIVE PULMONARY DISEASE. RATIONALE: AGE-RELATED DISEASES LIKE CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) OCCUR AT HIGHER RATES IN PEOPLE LIVING WITH HUMAN IMMUNODEFICIENCY VIRUS (PLWH) THAN IN UNINFECTED POPULATIONS. OBJECTIVES: TO IDENTIFY WHETHER ACCELERATED AGING CAN BE OBSERVED IN THE AIRWAYS OF PLWH WITH COPD, MANIFEST BY A UNIQUE DNA METHYLATION SIGNATURE. METHODS: BRONCHIAL EPITHELIAL BRUSHINGS FROM PLWH WITH AND WITHOUT COPD AND HIV-UNINFECTED ADULTS WITH AND WITHOUT COPD (N = 76) WERE PROFILED FOR DNA METHYLATION AND GENE EXPRESSION. WE EVALUATED GLOBAL ALU AND LINE-1 METHYLATION AND CALCULATED THE EPIGENETIC AGE USING THE HORVATH CLOCK AND THE METHYLATION TELOMERE LENGTH ESTIMATOR. TO IDENTIFY GENOME-WIDE DIFFERENTIAL DNA METHYLATION AND GENE EXPRESSION ASSOCIATED WITH HIV AND COPD, ROBUST LINEAR MODELS WERE USED FOLLOWED BY AN EXPRESSION QUANTITATIVE TRAIT METHYLATION (EQTM) ANALYSIS. MEASUREMENTS AND MAIN RESULTS: EPIGENETIC AGE ACCELERATION AND SHORTER METHYLATION ESTIMATES OF TELOMERE LENGTH WERE FOUND IN PLWH WITH COPD COMPARED WITH PLWH WITHOUT COPD AND UNINFECTED PATIENTS WITH AND WITHOUT COPD. GLOBAL HYPOMETHYLATION WAS IDENTIFIED IN PLWH. WE IDENTIFIED 7,970 CYTOSINE BASES LOCATED NEXT TO A GUANINE BASE (CPG SITES), 293 GENES, AND 9 EXPRESSION QUANTITATIVE TRAIT METHYLATION-GENE PAIRS ASSOCIATED WITH THE INTERACTION BETWEEN HIV AND COPD. ACTIN BINDING LIM PROTEIN FAMILY MEMBER 3 (ABLIM3) WAS ONE OF THE NOVEL CANDIDATE GENES FOR HIV-ASSOCIATED COPD HIGHLIGHTED BY OUR ANALYSIS. CONCLUSIONS: METHYLATION AGE ACCELERATION IS OBSERVED IN THE AIRWAY EPITHELIUM OF PLWH WITH COPD, A PROCESS THAT MAY BE RESPONSIBLE FOR THE HEIGHTENED RISK OF COPD IN THIS POPULATION. THEIR DISTINCT METHYLATION PROFILE, DIFFERING FROM THAT OBSERVED IN PATIENTS WITH COPD ALONE, SUGGESTS A UNIQUE PATHOGENESIS TO HIV-ASSOCIATED COPD. THE ASSOCIATIONS WARRANT FURTHER INVESTIGATION TO ESTABLISH CAUSALITY. 2022 13 3063 47 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