1 972 143 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 2 3056 43 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 3 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 4 6761 35 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 1343 42 DETECTING CORD BLOOD CELL TYPE-SPECIFIC EPIGENETIC ASSOCIATIONS WITH GESTATIONAL DIABETES MELLITUS AND EARLY CHILDHOOD GROWTH. BACKGROUND: EPIGENOME-WIDE ASSOCIATION STUDIES (EWAS) HAVE PROVIDED OPPORTUNITIES TO UNDERSTAND THE ROLE OF EPIGENETIC MECHANISMS IN DEVELOPMENT AND PATHOPHYSIOLOGY OF MANY CHRONIC DISEASES. HOWEVER, AN IMPORTANT LIMITATION OF CONVENTIONAL EWAS IS THAT PROFILES OF EPIGENETIC VARIABILITY ARE OFTEN OBTAINED IN SAMPLES OF MIXED CELL TYPES. HERE, WE AIM TO ASSESS WHETHER CHANGES IN CORD BLOOD DNA METHYLATION (DNAM) ASSOCIATED WITH GESTATIONAL DIABETES MELLITUS (GDM) EXPOSURE AND EARLY CHILDHOOD GROWTH MARKERS OCCUR IN A CELL TYPE-SPECIFIC MANNER. RESULTS: WE ANALYZED 275 CORD BLOOD SAMPLES COLLECTED AT DELIVERY FROM A PROSPECTIVE PRE-BIRTH COHORT WITH GENOME-WIDE DNAM PROFILED BY THE ILLUMINA METHYLATIONEPIC ARRAY. WE ESTIMATED PROPORTIONS OF SEVEN COMMON CELL TYPES IN EACH SAMPLE USING A CORD BLOOD-SPECIFIC DNAM REFERENCE PANEL. LEVERAGING A RECENTLY DEVELOPED APPROACH NAMED CELLDMC, WE PERFORMED CELL TYPE-SPECIFIC EWAS TO IDENTIFY CPG LOCI SIGNIFICANTLY ASSOCIATED WITH GDM, OR 3-YEAR-OLD BODY MASS INDEX (BMI) Z-SCORE. A TOTAL OF 1410 CPG LOCI DISPLAYED SIGNIFICANT CELL TYPE-SPECIFIC DIFFERENCES IN METHYLATION LEVEL BETWEEN 23 GDM CASES AND 252 CONTROLS WITH A FALSE DISCOVERY RATE < 0.05. GENE ONTOLOGY ENRICHMENT ANALYSIS INDICATED THAT LDL TRANSPORTATION EMERGED FROM CPG SPECIFICALLY IDENTIFIED FROM B-CELLS DNAM ANALYSES AND THE MITOGEN-ACTIVATED PROTEIN KINASE PATHWAY EMERGED FROM CPG SPECIFICALLY IDENTIFIED FROM NATURAL KILLER CELLS DNAM ANALYSES. IN ADDITION, WE IDENTIFIED FOUR AND SIX LOCI ASSOCIATED WITH 3-YEAR-OLD BMI Z-SCORE THAT WERE SPECIFIC TO CD8+ T-CELLS AND MONOCYTES, RESPECTIVELY. BY PERFORMING GENOME-WIDE PERMUTATION TESTS, WE VALIDATED THAT MOST OF OUR DETECTED SIGNALS HAD LOW FALSE POSITIVE RATES. CONCLUSION: COMPARED TO CONVENTIONAL EWAS ADJUSTING FOR THE EFFECTS OF CELL TYPE HETEROGENEITY, THE PROPOSED APPROACH BASED ON CELL TYPE-SPECIFIC EWAS COULD PROVIDE ADDITIONAL BIOLOGICALLY MEANINGFUL ASSOCIATIONS BETWEEN CPG METHYLATION, PRENATAL MATERNAL GDM OR 3-YEAR-OLD BMI. WITH CAREFUL VALIDATION, THESE FINDINGS MAY PROVIDE NEW INSIGHTS INTO THE PATHOGENESIS, PROGRAMMING, AND CONSEQUENCES OF RELATED CHILDHOOD METABOLIC DYSREGULATION. THEREFORE, WE PROPOSE THAT CELL TYPE-SPECIFIC ANALYSES ARE WORTH CAUTIOUS EXPLORATIONS. 2021 6 2418 38 EPIGENETIC SIGNATURE OF CHRONIC LOW BACK PAIN IN HUMAN T CELLS. OBJECTIVE: DETERMINE IF CHRONIC LOW BACK PAIN (LBP) IS ASSOCIATED WITH DNA METHYLATION SIGNATURES IN HUMAN T CELLS THAT WILL REVEAL NOVEL MECHANISMS AND POTENTIAL THERAPEUTIC TARGETS AND EXPLORE THE FEASIBILITY OF EPIGENETIC DIAGNOSTIC MARKERS FOR PAIN-RELATED PATHOPHYSIOLOGY. METHODS: GENOME-WIDE DNA METHYLATION ANALYSIS OF 850,000 CPG SITES IN WOMEN AND MEN WITH CHRONIC LBP AND PAIN-FREE CONTROLS WAS PERFORMED. T CELLS WERE ISOLATED (DISCOVERY COHORT, N = 32) AND USED TO IDENTIFY DIFFERENTIALLY METHYLATED CPG SITES, AND GENE ONTOLOGIES AND MOLECULAR PATHWAYS WERE IDENTIFIED. A POLYGENIC DNA METHYLATION SCORE FOR LBP WAS GENERATED IN BOTH WOMEN AND MEN. VALIDATION WAS PERFORMED IN AN INDEPENDENT COHORT (VALIDATION COHORT, N = 63) OF CHRONIC LBP AND HEALTHY CONTROLS. RESULTS: ANALYSIS WITH THE DISCOVERY COHORT REVEALED A TOTAL OF 2,496 AND 419 DIFFERENTIALLY METHYLATED CPGS IN WOMEN AND MEN, RESPECTIVELY. IN WOMEN, MOST OF THESE SITES WERE HYPOMETHYLATED AND ENRICHED IN GENES WITH FUNCTIONS IN THE EXTRACELLULAR MATRIX, IN THE IMMUNE SYSTEM (IE, CYTOKINES), OR IN EPIGENETIC PROCESSES. IN MEN, A UNIQUE CHRONIC LBP DNA METHYLATION SIGNATURE WAS IDENTIFIED CHARACTERIZED BY SIGNIFICANT ENRICHMENT FOR GENES FROM THE MAJOR HISTOCOMPATIBILITY COMPLEX. SEX-SPECIFIC POLYGENIC DNA METHYLATION SCORES WERE GENERATED TO ESTIMATE THE PAIN STATUS OF EACH INDIVIDUAL AND CONFIRMED IN THE VALIDATION COHORT USING PYROSEQUENCING. CONCLUSION: THIS STUDY REVEALS SEX-SPECIFIC DNA METHYLATION SIGNATURES IN HUMAN T CELLS THAT DISCRIMINATES CHRONIC LBP PARTICIPANTS FROM HEALTHY CONTROLS. 2021 7 812 51 CHANGES IN DNA METHYLATION PROFILES OF MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME PATIENTS REFLECT SYSTEMIC DYSFUNCTIONS. BACKGROUND: MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS) IS A LIFELONG DEBILITATING DISEASE WITH A COMPLEX PATHOLOGY NOT YET CLEARLY DEFINED. SUSCEPTIBILITY TO ME/CFS INVOLVES GENETIC PREDISPOSITION AND EXPOSURE TO ENVIRONMENTAL FACTORS, SUGGESTING AN EPIGENETIC ASSOCIATION. EPIGENETIC STUDIES WITH OTHER ME/CFS COHORTS HAVE USED ARRAY-BASED TECHNOLOGY TO IDENTIFY DIFFERENTIALLY METHYLATED INDIVIDUAL SITES. CHANGES IN RNA QUANTITIES AND PROTEIN ABUNDANCE HAVE BEEN DOCUMENTED IN OUR PREVIOUS INVESTIGATIONS WITH THE SAME ME/CFS COHORT USED FOR THIS STUDY. RESULTS: DNA FROM A WELL-CHARACTERISED NEW ZEALAND COHORT OF 10 ME/CFS PATIENTS AND 10 AGE-/SEX-MATCHED HEALTHY CONTROLS WAS ISOLATED FROM PERIPHERAL BLOOD MONONUCLEAR (PBMC) CELLS, AND USED TO GENERATE REDUCED GENOME-SCALE DNA METHYLATION MAPS USING REDUCED REPRESENTATION BISULPHITE SEQUENCING (RRBS). THE SEQUENCING DATA WERE ANALYSED UTILISING THE DMAP ANALYSIS PIPELINE TO IDENTIFY DIFFERENTIALLY METHYLATED FRAGMENTS, AND THE METHYLKIT PIPELINE WAS USED TO QUANTIFY METHYLATION DIFFERENCES AT INDIVIDUAL CPG SITES. DMAP IDENTIFIED 76 DIFFERENTIALLY METHYLATED FRAGMENTS AND METHYLKIT IDENTIFIED 394 DIFFERENTIALLY METHYLATED CYTOSINES THAT INCLUDED BOTH HYPER- AND HYPO-METHYLATION. FOUR CLUSTERS WERE IDENTIFIED WHERE DIFFERENTIALLY METHYLATED DNA FRAGMENTS OVERLAPPED WITH OR WERE WITHIN CLOSE PROXIMITY TO MULTIPLE DIFFERENTIALLY METHYLATED INDIVIDUAL CYTOSINES. THESE CLUSTERS IDENTIFIED REGULATORY REGIONS FOR 17 PROTEIN ENCODING GENES RELATED TO METABOLIC AND IMMUNE ACTIVITY. ANALYSIS OF DIFFERENTIALLY METHYLATED GENE BODIES (EXONS/INTRONS) IDENTIFIED 122 UNIQUE GENES. COMPARISON WITH OTHER STUDIES ON PBMCS FROM ME/CFS PATIENTS AND CONTROLS WITH ARRAY TECHNOLOGY SHOWED 59% OF THE GENES IDENTIFIED IN THIS STUDY WERE ALSO FOUND IN ONE OR MORE OF THESE STUDIES. FUNCTIONAL PATHWAY ENRICHMENT ANALYSIS IDENTIFIED 30 ASSOCIATED PATHWAYS. THESE INCLUDED IMMUNE, METABOLIC AND NEUROLOGICAL-RELATED FUNCTIONS DIFFERENTIALLY REGULATED IN ME/CFS PATIENTS COMPARED TO THE MATCHED HEALTHY CONTROLS. CONCLUSIONS: MAJOR DIFFERENCES WERE IDENTIFIED IN THE DNA METHYLATION PATTERNS OF ME/CFS PATIENTS THAT CLEARLY DISTINGUISHED THEM FROM THE HEALTHY CONTROLS. OVER HALF FOUND IN GENE BODIES WITH RRBS IN THIS STUDY HAD BEEN IDENTIFIED IN OTHER ME/CFS STUDIES USING THE SAME CELLS BUT WITH ARRAY TECHNOLOGY. WITHIN THE ENRICHED FUNCTIONAL IMMUNE, METABOLIC AND NEUROLOGICAL PATHWAYS, A NUMBER OF ENRICHED NEUROTRANSMITTER AND NEUROPEPTIDE REACTOME PATHWAYS HIGHLIGHTED A DISTURBED NEUROLOGICAL PATHOPHYSIOLOGY WITHIN THE PATIENT GROUP. 2020 8 3420 44 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 9 3557 39 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 10 4256 36 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 11 3063 38 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 14 1571 47 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 1586 42 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 16 3068 38 GENOME-WIDE DNA METHYLATION PROFILING IDENTIFIES DIFFERENTIAL METHYLATION IN UNINVOLVED PSORIATIC EPIDERMIS. PSORIASIS IS A CHRONIC INFLAMMATORY SKIN DISEASE WITH BOTH LOCAL AND SYSTEMIC COMPONENTS. GENOME-WIDE APPROACHES HAVE IDENTIFIED MORE THAN 60 PSORIASIS-SUSCEPTIBILITY LOCI, BUT GENES ARE ESTIMATED TO EXPLAIN ONLY ONE-THIRD OF THE HERITABILITY IN PSORIASIS, SUGGESTING ADDITIONAL, YET UNIDENTIFIED, SOURCES OF HERITABILITY. EPIGENETIC MODIFICATIONS HAVE BEEN LINKED TO PSORIASIS AND ALTERED DNA METHYLATION PATTERNS IN PSORIATIC VERSUS HEALTHY SKIN HAVE BEEN REPORTED IN WHOLE-SKIN BIOPSIES. IN THIS STUDY, FOCUSING ON EPIGENETIC MODIFICATIONS IN THE PSORIATIC UNINVOLVED SKIN, WE COMPARED THE LESIONAL AND NON-LESIONAL EPIDERMIS FROM PSORIASIS PATIENTS WITH EPIDERMIS FROM HEALTHY CONTROLS. WE PERFORMED AN EXHAUSTIVE GENOME-WIDE DNA METHYLATION PROFILING USING REDUCED REPRESENTATION BISULFITE SEQUENCING, WHICH INTERROGATES THE METHYLATION STATUS OF APPROXIMATELY 3-4 MILLION CPG SITES. MORE THAN 2,000 STRONGLY DIFFERENTIALLY METHYLATED SITES WERE IDENTIFIED AND A STRIKING OVERREPRESENTATION OF THE WNT AND CADHERIN PATHWAYS AMONG THE DIFFERENTIALLY METHYLATED SITES WAS FOUND. IN PARTICULAR, WE OBSERVE A STRONG DIFFERENTIAL METHYLATION IN SEVERAL PSORIASIS CANDIDATE GENES. A SUBSTANTIAL NUMBER OF DIFFERENTIALLY METHYLATED SITES PRESENT IN THE UNINVOLVED VERSUS HEALTHY EPIDERMIS SUGGESTS THE PRESENCE OF A PRE-PSORIATIC STATE IN THE CLINICALLY HEALTHY SKIN TYPE. OUR EXPLORATORY STUDY REPRESENTS A STARTING POINT FOR IDENTIFYING BIOMARKERS FOR PSORIASIS-PRONE SKIN BEFORE DISEASE ONSET. 2018 17 2079 35 EPIGENETIC DNA METHYLATION CHANGES ASSOCIATED WITH HEADACHE CHRONIFICATION: A RETROSPECTIVE CASE-CONTROL STUDY. BACKGROUND THE BIOLOGICAL MECHANISMS OF HEADACHE CHRONIFICATION ARE POORLY UNDERSTOOD. WE AIMED TO IDENTIFY CHANGES IN DNA METHYLATION ASSOCIATED WITH THE TRANSFORMATION FROM EPISODIC TO CHRONIC HEADACHE. METHODS PARTICIPANTS WERE RECRUITED FROM THE POPULATION-BASED NORWEGIAN HUNT STUDY. THIRTY-SIX FEMALE HEADACHE PATIENTS WHO TRANSFORMED FROM EPISODIC TO CHRONIC HEADACHE BETWEEN BASELINE AND FOLLOW-UP 11 YEARS LATER WERE MATCHED AGAINST 35 CONTROLS WITH EPISODIC HEADACHE. DNA METHYLATION WAS QUANTIFIED AT 485,000 CPG SITES, AND CHANGES IN METHYLATION LEVEL AT THESE SITES WERE COMPARED BETWEEN CASES AND CONTROLS BY LINEAR REGRESSION ANALYSIS. DATA WERE ANALYZED IN TWO STAGES (STAGES 1 AND 2) AND IN A COMBINED META-ANALYSIS. RESULTS NONE OF THE TOP 20 CPG SITES IDENTIFIED IN STAGE 1 REPLICATED IN STAGE 2 AFTER MULTIPLE TESTING CORRECTION. IN THE COMBINED META-ANALYSIS THE STRONGEST ASSOCIATED CPG SITES WERE RELATED TO SH2D5 AND NPTX2, TWO BRAIN-EXPRESSED GENES INVOLVED IN THE REGULATION OF SYNAPTIC PLASTICITY. FUNCTIONAL ENRICHMENT ANALYSIS POINTED TO PROCESSES INCLUDING CALCIUM ION BINDING AND ESTROGEN RECEPTOR PATHWAYS. CONCLUSION IN THIS FIRST GENOME-WIDE STUDY OF DNA METHYLATION IN HEADACHE CHRONIFICATION SEVERAL POTENTIALLY IMPLICATED LOCI AND PROCESSES WERE IDENTIFIED. THE STUDY EXEMPLIFIES THE USE OF PROSPECTIVELY COLLECTED POPULATION COHORTS TO SEARCH FOR EPIGENETIC MECHANISMS OF DISEASE. 2018 18 3079 53 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 19 785 35 CELL-TYPE SPECIFIC EWAS IDENTIFIES GENES INVOLVED IN HIV PATHOGENESIS AND ONCOGENESIS AMONG PEOPLE WITH HIV INFECTION. EPIGENOME-WIDE ASSOCIATION STUDIES (EWAS) OF HETEROGENOUS BLOOD CELLS HAVE IDENTIFIED CPG SITES ASSOCIATED WITH CHRONIC HIV INFECTION, WHICH OFFER LIMITED KNOWLEDGE OF CELL-TYPE SPECIFIC METHYLATION PATTERNS ASSOCIATED WITH HIV INFECTION. APPLYING A COMPUTATIONAL DECONVOLUTION METHOD VALIDATED BY CAPTURE BISULFITE DNA METHYLATION SEQUENCING, WE CONDUCTED A CELL TYPE-BASED EWAS AND IDENTIFIED DIFFERENTIALLY METHYLATED CPG SITES SPECIFIC FOR CHRONIC HIV INFECTION AMONG FIVE IMMUNE CELL TYPES IN BLOOD: CD4+ T-CELLS, CD8+ T-CELLS, B CELLS, NATURAL KILLER (NK) CELLS, AND MONOCYTES IN TWO INDEPENDENT COHORTS (N (TOTAL) =1,134). DIFFERENTIALLY METHYLATED CPG SITES FOR HIV-INFECTION WERE HIGHLY CONCORDANT BETWEEN THE TWO COHORTS. CELL-TYPE LEVEL META-EWAS REVEALED DISTINCT PATTERNS OF HIV-ASSOCIATED DIFFERENTIAL CPG METHYLATION, WHERE 67% OF CPG SITES WERE UNIQUE TO INDIVIDUAL CELL TYPES (FALSE DISCOVERY RATE, FDR <0.05). CD4+ T-CELLS HAD THE LARGEST NUMBER OF HIV-ASSOCIATED CPG SITES (N=1,472) COMPARED TO ANY OTHER CELL TYPE. GENES HARBORING STATISTICALLY SIGNIFICANT CPG SITES ARE INVOLVED IN IMMUNITY AND HIV PATHOGENESIS (E.G. CX3CR1 IN CD4+ T-CELLS, CCR7 IN B CELLS, IL12R IN NK CELLS, LCK IN MONOCYTES). MORE IMPORTANTLY, HIV-ASSOCIATED CPG SITES WERE OVERREPRESENTED FOR HALLMARK GENES INVOLVED IN CANCER PATHOLOGY ( FDR <0.05) (E.G. BCL FAMILY, PRDM16, PDCD1LGD, ESR1, DNMT3A, NOTCH2 ). HIV-ASSOCIATED CPG SITES WERE ENRICHED AMONG GENES INVOLVED IN HIV PATHOGENESIS AND ONCOGENESIS SUCH AS KRAS-SIGNALING, INTERFERON-ALPHA AND -GAMMA, TNF-ALPHA, INFLAMMATORY, AND APOPTOTIC PATHWAYS. OUR FINDINGS ARE NOVEL, UNCOVERING CELL-TYPE SPECIFIC MODIFICATIONS IN THE HOST EPIGENOME FOR PEOPLE WITH HIV THAT CONTRIBUTE TO THE GROWING BODY OF EVIDENCE REGARDING PATHOGEN-INDUCED EPIGENETIC ONCOGENICITY, SPECIFICALLY ON HIV AND ITS COMORBIDITY WITH CANCERS. 2023 20 1493 45 DNA HYPERMETHYLATION AND DNA HYPOMETHYLATION IS PRESENT AT DIFFERENT LOCI IN CHRONIC KIDNEY DISEASE. GENETIC RISK FACTORS FOR CHRONIC KIDNEY DISEASE (CKD) ARE BEING IDENTIFIED THROUGH INTERNATIONAL COLLABORATIONS. BY COMPARISON, EPIGENETIC RISK FACTORS FOR CKD HAVE ONLY RECENTLY BEEN CONSIDERED USING POPULATION-BASED APPROACHES. DNA METHYLATION IS A MAJOR EPIGENETIC MODIFICATION THAT IS ASSOCIATED WITH COMPLEX DISEASES, SO WE INVESTIGATED METHYLOME-WIDE LOCI FOR ASSOCIATION WITH CKD. A TOTAL OF 485,577 UNIQUE FEATURES WERE EVALUATED IN 255 INDIVIDUALS WITH CKD (CASES) AND 152 INDIVIDUALS WITHOUT EVIDENCE OF RENAL DISEASE (CONTROLS). FOLLOWING STRINGENT QUALITY CONTROL, RAW DATA WERE QUANTILE NORMALIZED AND BETA VALUES CALCULATED TO REFLECT THE METHYLATION STATUS AT EACH SITE. THE DIFFERENCE IN METHYLATION STATUS WAS EVALUATED BETWEEN CASES AND CONTROLS WITH RESULTANT P VALUES ADJUSTED FOR MULTIPLE TESTING. GENES WITH SIGNIFICANTLY INCREASED AND DECREASED LEVELS OF DNA METHYLATION WERE CONSIDERED FOR BIOLOGICAL RELEVANCE BY FUNCTIONAL ENRICHMENT ANALYSIS USING KEGG PATHWAYS IN PARTEK GENOMICS SUITE. TWENTY-THREE GENES, WHERE MORE THAN ONE CPG PER LOCI WAS IDENTIFIED WITH PADJUSTED<10(-8), DEMONSTRATED SIGNIFICANT METHYLATION CHANGES ASSOCIATED WITH CKD AND ADDITIONAL SUPPORT FOR THESE ASSOCIATED LOCI WAS SOUGHT FROM PUBLISHED LITERATURE. STRONG BIOLOGICAL CANDIDATES FOR CKD THAT SHOWED STATISTICALLY SIGNIFICANT DIFFERENTIAL METHYLATION INCLUDE CUX1, ELMO1, FKBP5, INHBA-AS1, PTPRN2, AND PRKAG2 GENES; SEVERAL GENES ARE DIFFERENTIALLY METHYLATED IN KIDNEY TISSUE AND RNA-SEQ SUPPORTS A FUNCTIONAL ROLE FOR DIFFERENTIAL METHYLATION IN ELMO1 AND PRKAG2 GENES. THIS STUDY REPORTS THE LARGEST, MOST COMPREHENSIVE, GENOME-WIDE QUANTITATIVE EVALUATION OF DNA METHYLATION FOR ASSOCIATION WITH CKD. EVIDENCE CONFIRMING METHYLATION SITES INFLUENCE DEVELOPMENT OF CKD WOULD STIMULATE RESEARCH TO IDENTIFY EPIGENETIC THERAPIES THAT MIGHT BE CLINICALLY USEFUL FOR CKD. 2014