1 3420 145 HUMAN LUNG DNA METHYLATION QUANTITATIVE TRAIT LOCI COLOCALIZE WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE GENOME-WIDE ASSOCIATION LOCI. RATIONALE: AS THE THIRD LEADING CAUSE OF DEATH IN THE UNITED STATES, THE IMPACT OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) MAKES IDENTIFICATION OF ITS MOLECULAR MECHANISMS OF GREAT IMPORTANCE. GENOME-WIDE ASSOCIATION STUDIES (GWASS) HAVE IDENTIFIED MULTIPLE GENOMIC REGIONS ASSOCIATED WITH COPD. HOWEVER, GENETIC VARIATION ONLY EXPLAINS A SMALL FRACTION OF THE SUSCEPTIBILITY TO COPD, AND SUB-GENOME-WIDE SIGNIFICANT LOCI MAY PLAY A ROLE IN PATHOGENESIS. OBJECTIVES: REGULATORY ANNOTATION WITH EPIGENETIC EVIDENCE MAY GIVE PRIORITY FOR FURTHER INVESTIGATION, PARTICULARLY FOR GWAS ASSOCIATIONS IN NONCODING REGIONS. WE PERFORMED INTEGRATIVE GENOMICS ANALYSES USING DNA METHYLATION PROFILING AND GENOME-WIDE SNP GENOTYPING FROM LUNG TISSUE SAMPLES FROM 90 SUBJECTS WITH COPD AND 36 CONTROL SUBJECTS. METHODS: WE PERFORMED METHYLATION QUANTITATIVE TRAIT LOCI (MQTL) ANALYSES, TESTING FOR SNPS ASSOCIATED WITH PERCENT DNA METHYLATION AND ASSESSED THE COLOCALIZATION OF THESE RESULTS WITH PREVIOUS COPD GWAS FINDINGS USING BAYESIAN METHODS IN THE R PACKAGE COLOC TO HIGHLIGHT POTENTIAL REGULATORY FEATURES OF THE LOCI. MEASUREMENTS AND MAIN RESULTS: WE IDENTIFIED 942,068 UNIQUE SNPS AND 33,996 UNIQUE CPG SITES AMONG THE SIGNIFICANT (5% FALSE DISCOVERY RATE) CIS-MQTL RESULTS. THE GENOME-WIDE SIGNIFICANT AND SUBTHRESHOLD (P < 10(-4)) GWAS SNPS WERE ENRICHED IN THE SIGNIFICANT MQTL SNPS (HYPERGEOMETRIC TEST P < 0.00001). WE OBSERVED ENRICHMENT FOR SITES LOCATED IN CPG SHORES AND SHELVES, BUT NOT CPG ISLANDS. USING BAYESIAN COLOCALIZATION, WE IDENTIFIED LOCI IN REGIONS NEAR KCNK3, EEFSEC, PIK3CD, DCDC2C, TCERG1L, FRMD4B, AND IL27. CONCLUSIONS: COLOCALIZATION OF MQTL AND GWAS LOCI PROVIDES REGULATORY CHARACTERIZATION OF SIGNIFICANT AND SUBTHRESHOLD GWAS FINDINGS, SUPPORTING A ROLE FOR GENETIC CONTROL OF METHYLATION IN COPD PATHOGENESIS. 2018 2 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 3 972 44 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 4 6761 39 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 5 57 48 A GENOME-WIDE ASSOCIATION STUDY OF QUANTITATIVE COMPUTED TOMOGRAPHIC EMPHYSEMA IN KOREAN POPULATIONS. EMPHYSEMA IS AN IMPORTANT FEATURE OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). GENETIC FACTORS LIKELY AFFECT EMPHYSEMA PATHOGENESIS, BUT THIS QUESTION HAS PREDOMINANTLY BEEN STUDIED IN THOSE OF EUROPEAN ANCESTRY. IN THIS STUDY, WE SOUGHT TO DETERMINE GENETIC COMPONENTS OF EMPHYSEMA SEVERITY AND CHARACTERIZE THE POTENTIAL FUNCTION OF THE ASSOCIATED LOCI IN KOREAN POPULATION. WE PERFORMED A GENOME-WIDE ASSOCIATION STUDY (GWAS) ON QUANTITATIVE EMPHYSEMA IN SUBJECTS WITH OR WITHOUT COPD FROM TWO KOREAN COPD COHORTS. WE INVESTIGATED THE FUNCTIONAL CONSEQUENCES OF THE LOCI USING EPIGENETIC ANNOTATION AND GENE EXPRESSION DATA. WE ALSO COMPARED OUR GWAS RESULTS WITH AN EPIGENOME-WIDE ASSOCIATION STUDY AND PREVIOUS DIFFERENTIAL GENE EXPRESSION ANALYSIS. IN TOTAL, 548 SUBJECTS (476 [86.9%] MALE) INCLUDING 514 COPD PATIENTS WERE EVALUATED. WE IDENTIFIED ONE GENOME-WIDE SIGNIFICANT SNP (P < 5.0 X 10(-8)), RS117084279, NEAR PIBF1. WE IDENTIFIED AN ADDITIONAL 57 SNPS (P < 5.0 X 10(-6)) ASSOCIATED WITH EMPHYSEMA IN ALL SUBJECTS, AND 106 SNPS (P < 5.0 X 10(-6)) IN COPD PATIENTS. OF THESE CANDIDATE SNPS, 2 (RS12459249, RS11667314) NEAR CYP2A6 WERE EXPRESSION QUANTITATIVE TRAIT LOCI IN LUNG TISSUE AND A SNP (RS11214944) NEAR NNMT WAS AN EXPRESSION QUANTITATIVE TRAIT LOCUS IN WHOLE BLOOD. OF NOTE, RS11214944 WAS IN LINKAGE DISEQUILIBRIUM WITH VARIANTS IN ENHANCER HISTONE MARKS IN LUNG TISSUE. SEVERAL GENES NEAR ADDITIONAL SNPS WERE IDENTIFIED IN OUR PREVIOUS EWAS STUDY WITH NOMINAL LEVEL OF SIGNIFICANCE. WE IDENTIFIED A NOVEL SNP ASSOCIATED WITH QUANTITATIVE EMPHYSEMA ON CT. INCLUDING THE NOVEL SNP, SEVERAL CANDIDATE SNPS IN OUR STUDY MAY PROVIDE CLUES TO THE GENETIC ETIOLOGY OF EMPHYSEMA IN ASIAN POPULATIONS. FURTHER RESEARCH AND VALIDATION OF THE LOCI WILL HELP DETERMINE THE GENETIC FACTORS FOR THE DEVELOPMENT OF EMPHYSEMA. 2021 6 3063 44 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