1 5222 89 PRIMARY BILIARY CIRRHOSIS: FAMILY STORIES. PRIMARY BILIARY CIRRHOSIS (PBC) IS A CHRONIC IMMUNE-MEDIATED CHOLESTATIC LIVER DISEASE OF UNKNOWN AETIOLOGY WHICH AFFECTS MOSTLY WOMEN IN MIDDLE AGE. FAMILIAL PBC IS WHEN PBC AFFECTS MORE THAN ONE MEMBER OF THE SAME FAMILY, AND DATA SUGGEST THAT FIRST-DEGREE RELATIVES OF PBC PATIENTS HAVE AN INCREASED RISK OF DEVELOPING THE DISEASE. MOST OFTEN, THESE FAMILIAL CLUSTERS INVOLVE MOTHER-DAUGHTER PAIRS, WHICH IS CONSISTENT WITH THE FEMALE PREPONDERANCE OF THE DISEASE. THESE CLUSTERS PROVIDE EVIDENCE TOWARDS A GENETIC BASIS UNDERLYING PBC. HOWEVER, CLUSTERS OF NONRELATED INDIVIDUALS HAVE ALSO BEEN REPORTED, GIVING STRENGTH TO AN ENVIRONMENTAL COMPONENT. TWIN STUDIES HAVE DEMONSTRATED A HIGH CONCORDANCE FOR PBC IN MONOZYGOTIC TWINS AND A LOW CONCORDANCE AMONG DIZYGOTIC TWINS. IN CONCLUSION, STUDIES OF PBC IN FAMILIES CLEARLY DEMONSTRATE THAT GENETIC, EPIGENETIC, AND ENVIRONMENTAL FACTORS PLAY A ROLE IN THE DEVELOPMENT OF THE DISEASE. 2011 2 4256 34 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 3 2142 38 EPIGENETIC INVESTIGATION OF VARIABLY X CHROMOSOME INACTIVATED GENES IN MONOZYGOTIC FEMALE TWINS DISCORDANT FOR PRIMARY BILIARY CIRRHOSIS. PRIMARY BILIARY CIRRHOSIS (PBC) IS AN AUTOIMMUNE CHRONIC CHOLESTATIC LIVER DISEASE WITH A STRONG GENETIC SUSCEPTIBILITY DUE TO THE HIGH CONCORDANCE IN MONOZYGOTIC (MZ) TWINS AND A STRIKING FEMALE PREDOMINANCE. WOMEN WITH PBC MANIFEST AN ENHANCED X MONOSOMY RATE IN PERIPHERAL LYMPHOCYTES AND WE THUS HYPOTHESIZED AN X CHROMOSOME EPIGENETIC COMPONENT TO EXPLAIN PBC FEMALE PREVALENCE. WHILE MOST GENES ON THE FEMALE INACTIVE X CHROMOSOME ARE SILENCED BY PROMOTER METHYLATION FOLLOWING X CHROMOSOME INACTIVATION (XCI), APPROXIMATELY 10% OF X- LINKED GENES EXHIBIT VARIABLE ESCAPE FROM XCI IN HEALTHY FEMALES. THIS STUDY WAS DESIGNED TO TEST THE HYPOTHESIS THAT SUSCEPTIBILITY TO PBC IS MODIFIED BY ONE OR MORE X-LINKED GENE WITH VARIABLE XCI STATUS. PERIPHERAL BLOOD MRNA AND DNA SAMPLES WERE OBTAINED FROM A UNIQUE COHORT OF MZ TWIN SETS DISCORDANT AND CONCORDANT FOR PBC. TRANSCRIPT LEVELS OF THE 125 VARIABLE XCI STATUS GENES WAS DETERMINED BY QUANTITATIVE RT-PCR ANALYSIS AND TWO GENES (CLIC2 AND PIN4) WERE IDENTIFIED AS CONSISTENTLY DOWNREGULATED IN THE AFFECTED TWIN OF DISCORDANT PAIRS. BOTH CLIC2 AND PIN4 DEMONSTRATED PARTIAL AND VARIABLE METHYLATION OF CPG SITES WITHIN 300 BP OF THE TRANSCRIPTION START SITE THAT DID NOT PREDICT THE XCI STATUS. PROMOTER METHYLATION OF CLIC2 MANIFESTED NO SIGNIFICANT DIFFERENCE BETWEEN SAMPLES AND NO SIGNIFICANT CORRELATION WITH TRANSCRIPT LEVELS. PIN4 METHYLATION SHOWED A POSITIVE TREND WITH TRANSCRIPTION IN ALL SAMPLES BUT NO DIFFERENTIAL METHYLATION WAS OBSERVED BETWEEN DISCORDANT TWINS. A GENETIC POLYMORPHISM AFFECTING THE NUMBER OF CPG SITES IN THE PIN4 PROMOTER DID NOT IMPACT METHYLATION OR TRANSCRIPT LEVELS IN A HETEROZYGOUS TWIN PAIR AND SHOWED A SIMILAR FREQUENCY IN INDEPENDENT SERIES OF UNRELATED PBC CASES AND CONTROLS. OUR RESULTS SUGGEST THAT EPIGENETIC FACTORS INFLUENCING PBC ONSET ARE MORE COMPLEX THAN METHYLATION DIFFERENCES AT X-LINKED PROMOTERS AND VARIABLY 3 INACTIVATED X-LINKED GENES MAY BE CHARACTERIZED BY PARTIAL PROMOTER METHYLATION AND BIALLELIC TRANSCRIPTION. 2011 4 3056 28 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 5 2643 24 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 6 1506 20 DNA METHYLATION AND IMMUNE CELL MARKERS DEMONSTRATE EVIDENCE OF ACCELERATED AGING IN PATIENTS WITH CHRONIC HEPATITIS B VIRUS OR HEPATITIS C VIRUS, WITH OR WITHOUT HUMAN IMMUNODEFICIENCT VIRUS CO-INFECTION. BACKGROUND: SEVERAL CHRONIC DISEASES ACCELERATE BIOLOGICAL AGING. WE INVESTIGATED AGE ACCELERATION AND THE ASSOCIATION BETWEEN PERIPHERAL BLOOD DNA METHYLATION (DNAM) AND IMMUNE CELL MARKERS IN PATIENTS CHRONICALLY INFECTED WITH THE HEPATITIS B VIRUS (HBV) OR THE HEPATITIS C VIRUS (HCV) WITH AND WITHOUT HUMAN IMMUNODEFICIENCY VIRUS (HIV) CO-INFECTION. METHODS: AGE ACCELERATION WAS MEASURED AS THE DIFFERENCE BETWEEN EPIGENETIC AGE (HORVATH CLOCK) AND CHRONOLOGICAL AGE. THE IMMUNE MARKER MODEL OF AGE ACCELERATION WAS DEVELOPED USING ELASTIC NET REGRESSION TO SELECT BOTH THE IMMUNE MARKERS AND THEIR ASSOCIATED WEIGHTS IN THE FINAL LINEAR MODEL. RESULTS: PATIENTS WITH CHRONIC HBV (N = 51) HAD A SIGNIFICANTLY HIGHER MEDIAN EPIGENETIC AGE COMPARED TO CHRONOLOGICAL AGE (AGE ACCELERATED) (P < .001). IN PATIENTS WITH CHRONIC HCV INFECTION (N = 63), AGE ACCELERATION WAS ASSOCIATED WITH LIVER FIBROSIS AS ASSESSED BY HISTOLOGY (P < .05), OR PRESENCE OF HIV CO-INFECTION (P < .05), BUT NOT HCV MONO-INFECTION. AGE ACCELERATION DEFINED BY IMMUNE MARKERS WAS CONCORDANT WITH AGE ACCELERATION BY DNA METHYLATION (CORRELATION COEFFICIENT = .59 IN HBV; P = .0025). ONE-YEAR TREATMENT OF HBV PATIENTS WITH NUCLEOSIDE THERAPY WAS ASSOCIATED WITH A MODEST REDUCTION IN AGE ACCELERATION, AS MEASURED USING THE IMMUNE MARKER MODEL (-.65 YEARS, P = .018). CONCLUSION: OUR FINDINGS SUGGEST THAT PATIENTS WITH CHRONIC VIRAL HEPATITIS HAVE ACCELERATED EPIGENETIC AGING, THAT IMMUNE MARKERS DEFINE BIOLOGICAL AGE, AND HAVE THE POTENTIAL TO ASSESS THE EFFECTS OF THERAPEUTIC INTERVENTION ON AGE ACCELERATION. 2021 7 4775 31 NUCLEIC ACID-SENSING AND INTERFERON-INDUCIBLE PATHWAYS SHOW DIFFERENTIAL METHYLATION IN MZ TWINS DISCORDANT FOR LUPUS AND OVEREXPRESSION IN INDEPENDENT LUPUS SAMPLES: IMPLICATIONS FOR PATHOGENIC MECHANISM AND DRUG TARGETING. SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) IS A CHRONIC, MULTISYSTEM, AUTOIMMUNE INFLAMMATORY DISEASE WITH GENOMIC AND NON-GENOMIC CONTRIBUTIONS TO RISK. WE HYPOTHESIZE THAT EPIGENETIC FACTORS ARE A SIGNIFICANT CONTRIBUTOR TO SLE RISK AND MAY BE INFORMATIVE FOR IDENTIFYING PATHOGENIC MECHANISMS AND THERAPEUTIC TARGETS. TO TEST THIS HYPOTHESIS WHILE CONTROLLING FOR GENETIC BACKGROUND, WE PERFORMED AN EPIGENOME-WIDE ANALYSIS OF DNA METHYLATION IN GENOMIC DNA FROM WHOLE BLOOD IN THREE PAIRS OF FEMALE MONOZYGOTIC (MZ) TWINS OF EUROPEAN ANCESTRY, DISCORDANT FOR SLE. RESULTS WERE REPLICATED ON THE SAME ARRAY IN FOUR CELL TYPES FROM A SET OF FOUR DANISH FEMALE MZ TWIN PAIRS DISCORDANT FOR SLE. GENES IMPLICATED BY THE EPIGENETIC ANALYSES WERE THEN EVALUATED IN 10 INDEPENDENT SLE GENE EXPRESSION DATASETS FROM THE GENE EXPRESSION OMNIBUS (GEO). THERE WERE 59 DIFFERENTIALLY METHYLATED LOCI BETWEEN UNAFFECTED AND AFFECTED MZ TWINS IN WHOLE BLOOD, INCLUDING 11 NOVEL LOCI. ALL BUT TWO OF THESE LOCI WERE HYPOMETHYLATED IN THE SLE TWINS RELATIVE TO THE UNAFFECTED TWINS. THE GENES HARBORING THESE HYPOMETHYLATED LOCI EXHIBITED INCREASED EXPRESSION IN MULTIPLE INDEPENDENT DATASETS OF SLE PATIENTS. THIS PATTERN WAS LARGELY CONSISTENT REGARDLESS OF DISEASE ACTIVITY, CELL TYPE, OR RENAL TISSUE TYPE. THE GENES PROXIMAL TO CPGS EXHIBITING DIFFERENTIAL METHYLATION (DM) IN THE SLE-DISCORDANT MZ TWINS AND EXHIBITING DIFFERENTIAL EXPRESSION (DE) IN INDEPENDENT SLE GEO COHORTS (DM-DE GENES) CLUSTERED INTO TWO PATHWAYS: THE NUCLEIC ACID-SENSING PATHWAY AND THE TYPE I INTERFERON PATHWAY. THE DM-DE GENES WERE ALSO INFORMATICALLY QUERIED FOR POTENTIAL GENE-DRUG INTERACTIONS, YIELDING A LIST OF 41 DRUGS INCLUDING A KNOWN SLE THERAPY. THE DM-DE GENES DELINEATE TWO IMPORTANT BIOLOGIC PATHWAYS THAT ARE NOT ONLY REFLECTIVE OF THE HETEROGENEITY OF SLE BUT MAY ALSO CORRELATE WITH DISTINCT IFN RESPONSES THAT DEPEND ON THE SOURCE, TYPE, AND LOCATION OF NUCLEIC ACID MOLECULES AND THE ACTIVATED RECEPTORS IN INDIVIDUAL PATIENTS. CELL- AND TISSUE-SPECIFIC ANALYSES WILL BE CRITICAL TO THE UNDERSTANDING OF GENETIC FACTORS DYSREGULATING THE NUCLEIC ACID-SENSING AND IFN PATHWAYS AND WHETHER THESE FACTORS COULD BE APPROPRIATE TARGETS FOR THERAPEUTIC INTERVENTION. 2021 8 6761 26 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 9 561 33 BARIATRIC SURGERY-INDUCED WEIGHT LOSS AND ASSOCIATED GENOME-WIDE DNA-METHYLATION ALTERATIONS IN OBESE INDIVIDUALS. BACKGROUND: OBESITY IS A MULTIFACTORIAL AND CHRONIC CONDITION OF GROWING UNIVERSAL CONCERN. IT HAS RECENTLY BEEN REPORTED THAT BARIATRIC SURGERY IS A MORE SUCCESSFUL TREATMENT FOR SEVERE OBESITY THAN OTHER NONINVASIVE INTERVENTIONS, RESULTING IN RAPID SIGNIFICANT WEIGHT LOSS AND ASSOCIATED CHRONIC DISEASE REMISSION. THE IDENTIFICATION OF DISTINCT EPIGENETIC PATTERNS IN PATIENTS WHO ARE OBESE OR HAVE METABOLIC IMBALANCES HAS SUGGESTED A POTENTIAL ROLE FOR EPIGENETIC ALTERATIONS IN CAUSAL OR MEDIATING PATHWAYS IN THE DEVELOPMENT OF OBESITY-RELATED PATHOLOGIES. SPECIFIC CHANGES IN THE EPIGENOME (DNA METHYLOME), ASSOCIATED WITH METABOLIC DISORDERS, CAN BE DETECTED IN THE BLOOD. WE INVESTIGATED WHETHER SUCH EPIGENETIC CHANGES ARE REVERSIBLE AFTER WEIGHT LOSS USING GENOME-WIDE DNA METHYLOME ANALYSIS OF BLOOD SAMPLES FROM INDIVIDUALS WITH SEVERE OBESITY (MEAN BMI ~ 45) UNDERGOING BARIATRIC SURGERY. RESULTS: OUR ANALYSIS REVEALED 41 SIGNIFICANT (BONFERRONI P < 0.05) AND 1169 (FALSE DISCOVERY RATE P < 0.05) SUGGESTIVE DIFFERENTIALLY METHYLATED POSITIONS (DMPS) ASSOCIATED WITH WEIGHT LOSS DUE TO BARIATRIC SURGERY. AMONG THE 41 SIGNIFICANT DMPS, 5 CPGS WERE REPLICATED IN AN INDEPENDENT COHORT OF BMI-DISCORDANT MONOZYGOTIC TWINS (THE HEAVIER TWIN UNDERWENT DIET-INDUCED WEIGHT LOSS). THE EFFECT SIZES OF THESE 5 CPGS WERE CONSISTENT ACROSS DISCOVERY AND REPLICATION SETS (P < 0.05). WE ALSO IDENTIFIED 192 DIFFERENTIALLY METHYLATED REGIONS (DMRS) AMONG WHICH SMAD6 AND PFKFB3 GENES WERE THE TOP HYPERMETHYLATED AND HYPOMETHYLATED REGIONS, RESPECTIVELY. PATHWAY ENRICHMENT ANALYSIS OF THE DMR-ASSOCIATED GENES SHOWED THAT FUNCTIONAL PATHWAYS RELATED TO IMMUNE FUNCTION AND TYPE 1 DIABETES WERE SIGNIFICANT. WEIGHT LOSS DUE TO BARIATRIC SURGERY ALSO SIGNIFICANTLY DECELERATED EPIGENETIC AGE 12 MONTHS AFTER THE INTERVENTION (MEAN = - 4.29; P = 0.02). CONCLUSIONS: WE IDENTIFIED WEIGHT LOSS-ASSOCIATED DNA-METHYLATION ALTERATIONS TARGETING IMMUNE AND INFLAMMATORY GENE PATHWAYS IN BLOOD SAMPLES FROM BARIATRIC-SURGERY PATIENTS. THE TOP HITS WERE REPLICATED IN SAMPLES FROM AN INDEPENDENT COHORT OF BMI-DISCORDANT MONOZYGOTIC TWINS FOLLOWING A HYPOCALORIC DIET. ENERGY RESTRICTION AND BARIATRIC SURGERY THUS SHARE CPGS THAT MAY REPRESENT EARLY INDICATORS OF RESPONSE TO THE METABOLIC EFFECTS OF WEIGHT LOSS. THE ANALYSIS OF BARIATRIC SURGERY-ASSOCIATED DMRS SUGGESTS THAT EPIGENETIC REGULATION OF GENES INVOLVED IN ENDOTHELIAL AND ADIPOSE TISSUE FUNCTION IS KEY IN THE PATHOPHYSIOLOGY OF OBESITY. 2022 10 404 26 ANALYSIS OF EPIGENETIC AGE PREDICTORS IN PAIN-RELATED CONDITIONS. CHRONIC PAIN PREVALENCE IS HIGH WORLDWIDE AND INCREASES AT OLDER AGES. SIGNS OF PREMATURE AGING HAVE BEEN ASSOCIATED WITH CHRONIC PAIN, BUT FEW STUDIES HAVE INVESTIGATED AGING BIOMARKERS IN PAIN-RELATED CONDITIONS. A SET OF DNA METHYLATION (DNAM)-BASED ESTIMATES OF AGE, CALLED "EPIGENETIC CLOCKS," HAS BEEN PROPOSED AS BIOLOGICAL MEASURES OF AGE-RELATED ADVERSE PROCESSES, MORBIDITY, AND MORTALITY. THE AIM OF THIS STUDY IS TO ASSESS IF DIFFERENT PAIN-RELATED PHENOTYPES SHOW ALTERATIONS IN DNAM AGE. IN OUR ANALYSIS, WE CONSIDERED THREE COHORTS FOR WHICH WHOLE-BLOOD DNAM DATA WERE AVAILABLE: HEAT PAIN SENSITIVITY (HPS), INCLUDING 20 MONOZYGOTIC TWIN PAIRS DISCORDANT FOR HEAT PAIN TEMPERATURE THRESHOLD; FIBROMYALGIA (FM), INCLUDING 24 CASES AND 20 CONTROLS; AND HEADACHE, INCLUDING 22 CHRONIC MIGRAINE AND MEDICATION OVERUSE HEADACHE PATIENTS (MOH), 18 EPISODIC MIGRAINEURS (EM), AND 13 HEALTHY SUBJECTS. WE USED THE HORVATH'S EPIGENETIC AGE CALCULATOR TO OBTAIN DNAM-BASED ESTIMATES OF EPIGENETIC AGE, TELOMERE LENGTH, LEVELS OF 7 PROTEINS IN PLASMA, NUMBER OF SMOKED PACKS OF CIGARETTES PER YEAR, AND BLOOD CELL COUNTS. WE DID NOT FIND DIFFERENCES IN EPIGENETIC AGE ACCELERATION, CALCULATED USING FIVE DIFFERENT EPIGENETIC CLOCKS, BETWEEN SUBJECTS DISCORDANT FOR PAIN-RELATED PHENOTYPES. TWINS WITH HIGH HPS HAD INCREASED CD8+ T CELL COUNTS (NOMINAL P = 0.028). HPS THRESHOLDS WERE NEGATIVELY ASSOCIATED WITH ESTIMATED LEVELS OF GDF15 (NOMINAL P = 0.008). FM PATIENTS SHOWED DECREASED NAIVE CD4+ T CELL COUNTS COMPARED WITH CONTROLS (NOMINAL P = 0.015). THE SEVERITY OF FM MANIFESTATIONS EXPRESSED THROUGH VARIOUS EVALUATION TESTS WAS ASSOCIATED WITH DECREASED LEVELS OF LEPTIN, SHORTER LENGTH OF TELOMERES, AND REDUCED CD8+ T AND NATURAL KILLER CELL COUNTS (NOMINAL P < 0.05), WHILE THE DURATION OF PAINFUL SYMPTOMS WAS POSITIVELY ASSOCIATED WITH TELOMERE LENGTH (NOMINAL P = 0.034). NO DIFFERENCES IN DNAM-BASED ESTIMATES WERE DETECTED FOR MOH OR EM COMPARED WITH CONTROLS. IN SUMMARY, OUR STUDY SUGGESTS THAT HPS, FM, AND MOH/EM DO NOT SHOW SIGNS OF EPIGENETIC AGE ACCELERATION IN WHOLE BLOOD, WHILE HPS AND FM ARE ASSOCIATED WITH DNAM-BASED ESTIMATES OF IMMUNOLOGICAL PARAMETERS, PLASMA PROTEINS, AND TELOMERE LENGTH. FUTURE STUDIES SHOULD EXTEND THESE OBSERVATIONS IN LARGER COHORTS. 2020 11 972 19 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 3557 27 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 13 5744 16 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 14 2622 23 EPIGENOME-WIDE ASSOCIATION STUDIES IN ASTHMA: A SYSTEMATIC REVIEW. OBJECTIVE: ASTHMA IS A COMMON CHRONIC RESPIRATORY AIRWAY DISEASE INFLUENCED BY ENVIRONMENTAL FACTORS AND POSSIBLY THEIR INTERACTION WITH THE HUMAN GENOME CAUSING EPIGENETIC CHANGES. EPIGENOME-WIDE ASSOCIATION STUDIES (EWAS) HAVE MAINLY INVESTIGATED DNA METHYLATION AND ITS ASSOCIATION WITH DISEASE OR TRAITS, EXPOSURE FACTORS OR GENE EXPRESSION. THIS SYSTEMATIC REVIEW AIMED TO IDENTIFY ALL EWAS ASSESSING DIFFERENTIALLY METHYLATED SITES ASSOCIATED WITH ASTHMA IN HUMANS. DESIGN: STRUCTURED SYSTEMATIC LITERATURE SEARCH FOLLOWING PRISMA GUIDELINES, NEWCASTLE-OTTAWA SCALE (NOS) FOR COHORT STUDIES WAS USED FOR BIAS ASSESSMENT. DATA SOURCES: WE SEARCHED PUBMED AND EMBASE DATABASES FROM 2005 TO 2019. ELIGIBILITY CRITERIA: EPIGENOME-WIDE ASSOCIATION STUDIES TESTING ASSOCIATION BETWEEN DIFFERENTIAL METHYLATION AND ASTHMA IN HUMANS. RESULTS: OVERALL, WE IDENTIFIED 16 EWAS STUDIES COMPLYING WITH OUR SEARCH CRITERIA. TWELVE STUDIES WERE CONDUCTED ON CHILDREN, AND 10 WERE CONDUCTED ON SAMPLE SIZES <150 SUBJECTS. FOUR HUNDRED AND NINETEEN CPGS WERE REPORTED IN CHILDREN STUDIES AFTER CORRECTION FOR MULTIPLE TESTING. IN THE ADULT STUDIES, THOUSANDS OF DIFFERENTIALLY METHYLATED SITES WERE IDENTIFIED. DIFFERENTIAL METHYLATION IN INFLAMMATORY-RELATED GENES CORRELATED WITH HIGHER LEVELS OF GENE EXPRESSIONS OF INFLAMMATORY MODULATORS IN ASTHMA. DIFFERENTIALLY METHYLATED GENES ASSOCIATED WITH ASTHMA INCLUDED SMAD3, SERPINC1, PROK1, IL13, RUNX3 AND TIGIT. FORTY-ONE CPGS WERE REPLICATED AT LEAST ONCE IN BLOOD SAMPLES, AND 28 CPGS WERE REPLICATED IN NASAL SAMPLES. CONCLUSION: ALTHOUGH MANY DIFFERENTIALLY METHYLATED CPGS IN GENES KNOWN TO BE INVOLVED IN ASTHMA HAVE BEEN IDENTIFIED IN EWAS TO DATE, WE CONCLUDE THAT FURTHER STUDIES OF LARGER SAMPLE SIZES AND ANALYSES OF DIFFERENTIAL METHYLATION BETWEEN DIFFERENT PHENOTYPES ARE NEEDED IN ORDER TO COMPREHENSIVELY EVALUATE THE ROLE OF EPIGENETIC FACTORS IN THE PATHOPHYSIOLOGY AND HETEROGENEITY OF ASTHMA, AND THE POTENTIAL CLINICAL UTILITY TO PREDICT OR CLASSIFY PATIENTS WITH ASTHMA. 2019 15 1672 26 DRD4 METHYLATION AS A POTENTIAL BIOMARKER FOR PHYSICAL AGGRESSION: AN EPIGENOME-WIDE, CROSS-TISSUE INVESTIGATION. EPIGENETIC PROCESSES THAT REGULATE GENE EXPRESSION, SUCH AS DNA METHYLATION (DNAM), HAVE BEEN LINKED TO INDIVIDUAL DIFFERENCES IN PHYSICAL AGGRESSION. YET, IT IS CURRENTLY UNCLEAR WHETHER: (A) DNAM PATTERNS IN HUMANS ASSOCIATE WITH PHYSICAL AGGRESSION INDEPENDENTLY OF OTHER CO-OCCURRING PSYCHIATRIC AND BEHAVIORAL SYMPTOMS; (B) WHETHER THESE PATTERNS ARE OBSERVABLE ACROSS MULTIPLE TISSUES; AND (C) WHETHER THEY MAY FUNCTION AS A CAUSAL VERSUS NONCAUSAL BIOMARKER OF PHYSICAL AGGRESSION. HERE, WE USED A MULTISAMPLE, CROSS-TISSUE DESIGN TO ADDRESS THESE QUESTIONS. FIRST, WE EXAMINED GENOME-WIDE DNAM PATTERNS (BUCCAL SWABS; ILLUMINA 450K) ASSOCIATED WITH ENGAGEMENT IN PHYSICAL FIGHTS IN A SAMPLE OF HIGH-RISK YOUTH (N = 119; AGE = 16-24 YEARS; 53% FEMALE). WE IDENTIFIED ONE DIFFERENTIALLY METHYLATED REGION IN DRD4, WHICH SURVIVED GENOME-WIDE CORRECTION, ASSOCIATED WITH PHYSICAL AGGRESSION ABOVE AND BEYOND CO-OCCURRING SYMPTOMATOLOGY (E.G., ADHD, SUBSTANCE USE), AND SHOWED STRONG CROSS-TISSUE CONCORDANCE WITH BOTH BLOOD AND BRAIN. SECOND, WE FOUND THAT DNAM SITES WITHIN THIS REGION WERE ALSO DIFFERENTIALLY METHYLATED IN AN INDEPENDENT SAMPLE OF YOUNG ADULTS, BETWEEN INDIVIDUALS WITH A HISTORY OF CHRONIC-HIGH VERSUS LOW PHYSICAL AGGRESSION (PERIPHERAL T CELLS; AGES 26-28). FINALLY, WE RAN A MENDELIAN RANDOMIZATION ANALYSIS USING GWAS DATA FROM THE EAGLE CONSORTIUM TO TEST FOR A CAUSAL ASSOCIATION OF DRD4 METHYLATION WITH PHYSICAL AGGRESSION. ONLY ONE GENETIC INSTRUMENT WAS ELIGIBLE FOR THE ANALYSIS, AND RESULTS PROVIDED NO EVIDENCE FOR A CAUSAL ASSOCIATION. OVERALL, OUR FINDINGS LEND SUPPORT FOR PERIPHERAL DRD4 METHYLATION AS A POTENTIAL BIOMARKER OF PHYSICALLY AGGRESSIVE BEHAVIOR, WITH NO EVIDENCE YET OF A CAUSAL RELATIONSHIP. 2018 16 1343 24 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 17 824 21 CHARACTERIZATION OF COPY NUMBER ALTERATIONS IN A MOUSE MODEL OF FIBROSIS-ASSOCIATED HEPATOCELLULAR CARCINOMA REVEALS CONCORDANCE WITH HUMAN DISEASE. HEPATOCELLULAR CARCINOMA (HCC) IS A PREVALENT HUMAN CANCER WITH RISING INCIDENCE WORLDWIDE. HUMAN HCC IS FREQUENTLY ASSOCIATED WITH CHRONIC LIVER INFLAMMATION AND CIRRHOSIS, PATHOPHYSIOLOGICAL PROCESSES THAT ARE A CONSEQUENCE OF CHRONIC VIRAL INFECTION, DISTURBANCES IN METABOLISM, OR EXPOSURE TO CHEMICAL TOXICANTS. TO BETTER CHARACTERIZE THE PATHOGENESIS OF HCC, WE USED A HUMAN DISEASE-RELEVANT MOUSE MODEL OF FIBROSIS-ASSOCIATED HEPATOCARCINOGENESIS. IN THIS MODEL, MARKED LIVER TUMOR RESPONSE CAUSED BY THE PROMUTAGENIC CHEMICAL N-NITROSODIETHYLAMINE IN THE PRESENCE OF LIVER FIBROSIS WAS ASSOCIATED WITH EPIGENETIC EVENTS INDICATIVE OF GENOMIC INSTABILITY. THEREFORE, WE HYPOTHESIZED THAT DNA COPY NUMBER ALTERATIONS (CNAS), A FEATURE OF GENOMIC INSTABILITY AND A COMMON CHARACTERISTIC OF CANCER, ARE CONCORDANT BETWEEN HUMAN HCC AND MOUSE MODELS OF FIBROSIS-ASSOCIATED HEPATOCARCINOGENESIS. WE EVALUATED DNA CNAS AND CHANGES IN GENE EXPRESSION IN THE MOUSE LIVER (NORMAL, TUMOR, AND NONTUMOR FIBROTIC TISSUES). ADDITIONALLY, WE COMPARED OUR FINDINGS TO DNA CNAS IN HUMAN HCC CASES (TUMOR AND NONTUMOR CIRRHOTIC/FIBROTIC TISSUES) USING PUBLICLY AVAILABLE DATA FROM THE CANCER GENOME ATLAS (TCGA). WE OBSERVED THAT WHILE FIBROTIC LIVER TISSUE IS LARGELY DEVOID OF DNA CNAS, HIGHLY FREQUENTLY OCCURRING DNA CNAS ARE FOUND IN MOUSE TUMORS, WHICH IS INDICATIVE OF A PROFOUND INCREASE IN CHROMOSOMAL INSTABILITY IN HCC. THE CROSS-SPECIES GENE-LEVEL COMPARISON OF CNAS IDENTIFIED SHARED REGIONS OF CNAS BETWEEN HUMAN FIBROSIS- AND CIRRHOSIS-ASSOCIATED LIVER TUMORS AND MOUSE FIBROSIS-ASSOCIATED HCC. OUR RESULTS SUGGEST THAT CNAS MOST COMMONLY ARISE IN NEOPLASTIC TISSUE RATHER THAN IN FIBROTIC OR CIRRHOTIC LIVER, AND DEMONSTRATE THE UTILITY OF THIS MOUSE MODEL IN REPLICATING THE MOLECULAR FEATURES OF HUMAN HCC. 2016 18 785 20 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 19 812 30 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 20 6415 16 THE STUDY OF P16 AND P15 GENE METHYLATION IN HEAD AND NECK SQUAMOUS CELL CARCINOMA AND THEIR QUANTITATIVE EVALUATION IN PLASMA BY REAL-TIME PCR. EPIGENETIC SILENCING OF THE P16 AND P15 GENES BY PROMOTER METHYLATION ARE COMMONLY OBSERVED IN HUMAN EPITHELIAL MALIGNANCIES, INCLUDING HEAD AND NECK SQUAMOUS CELL CARCINOMAS (HNSCC). IN THIS STUDY, A METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP) WAS USED TO EVALUATE THE METHYLATION STATUS OF THE P16 AND P15 GENES IN 73 HNSCC SURGICAL SPECIMENS. P16 AND P15 GENE METHYLATION WAS ALSO EXAMINED IN 29 PAIRED METASTATIC LYMPH NODES AND 29 PAIRED HISTOLOGICALLY, NORMAL RESECTION MARGIN MUCOSAE. THE QUANTITY OF CELL-FREE METHYLATED P16 AND P15 DNA IN THE PLASMA SAMPLES OF 20 HNSCC PATIENTS AND 24 HEALTHY CONTROLS WAS ALSO EXAMINED USING A FLUORESCENCE-BASED REAL-TIME PCR ASSAY. THE FREQUENCIES OF P16 AND P15 METHYLATION IN THE PRIMARY TUMOUR WERE 49% AND 60%, RESPECTIVELY. CONCORDANT METHYLATION OF P16 AND P15 IN TUMOUR SAMPLES AND METASTATIC LYMPH NODES WAS FOUND IN 59 AND 38% OF CASES, RESPECTIVELY. A SIGNIFICANTLY HIGHER PREVALENCE OF P15 METHYLATION WAS FOUND IN HISTOLOGICALLY-NORMAL SURGICAL MARGIN EPITHELIA OF HNSCC PATIENTS WITH CHRONIC SMOKING AND DRINKING HABITS COMPARED WITH NON-SMOKERS AND NON-DRINKERS. IN ADDITION, METHYLATED P16 AND P15 DNA LEVELS WERE SIGNIFICANTLY HIGHER IN THE PLASMA OF HNSCC PATIENTS (MEAN 56 COPIES/ML PLASMA AND 65 COPIES/ML PLASMA, RESPECTIVELY) COMPARED WITH NORMAL CONTROLS (MEAN 6 COPIES/ML PLASMA AND 16 COPIES/ML PLASMA, RESPECTIVELY). IN CONCLUSION, PROMOTER METHYLATION OF THE P16 AND P15 GENES IS INVOLVED IN THE PATHOGENESIS OF HNSCC AND MAY BE RELATED TO CHRONIC SMOKING AND DRINKING. THE DIFFERENTIAL LEVELS OF METHYLATED P16 AND P15 DNA IN PLASMA MIGHT BE POTENTIAL USEFUL MARKERS IN SCREENING HIGH-RISK POPULATIONS FOR EARLY HNSCC AND MONITORING THEIR TREATMENT RESPONSE. 2003