1 3046 137 GENOME-WIDE ANALYSIS OF DNA METHYLATION IDENTIFIES S100A13 AS AN EPIGENETIC BIOMARKER IN INDIVIDUALS WITH CHRONIC (>/= 30 YEARS) TYPE 2 DIABETES WITHOUT DIABETIC RETINOPATHY. BACKGROUND: THIS STUDY AIMED TO DETERMINE THE EPIGENETIC BIOMARKERS OF DIABETIC RETINOPATHY (DR) IN SUBJECTS WITH TYPE 2 DIABETES MELLITUS (T2DM). THIS RETROSPECTIVE STUDY IS BASED ON THE SHANGHAI XINJING COMMUNITY PREVENTION AND TREATMENT ADMINISTRATIVE SYSTEM OF CHRONIC DISEASES. THE SUBJECTS ENROLLED HEREIN WERE T2DM PATIENTS WHO HAD UNDERGONE LONG-TERM FOLLOW-UP EVALUATION IN THE SYSTEM. TWO CONSECUTIVE STUDIES WERE CONDUCTED. IN THE DISCOVERY COHORT, AMONG 19 SUBJECTS WHO HAD DEVELOPED DR WITH A DM DURATION < 3 YEARS AND 21 SUBJECTS WITHOUT DR > 30 YEARS AFTER BEING DIAGNOSED WITH DM, AN INFINIUM HUMAN METHYLATION 850 BEADCHIP WAS USED TO IDENTIFY DIFFERENTIAL METHYLATION REGIONS (DMRS) AND DIFFERENTIAL METHYLATION SITES (DMSS). THE FUNCTION OF THE GENES WAS ASSESSED THROUGH KEGG ENRICHMENT ANALYSIS, GENE ONTOLOGY (GO) ANALYSIS, AND PATHWAY NETWORK ANALYSIS. IN THE REPLICATION COHORT, 87 DR PATIENTS WITH A SHORT DM DURATION AND 89 PATIENTS WITHOUT DR OVER A DM DURATION > 20 YEARS WERE COMPARED TO ASSESS THE ASSOCIATION BETWEEN DMSS AND DR UPON PYROSEQUENCING. RESULTS: A TOTAL OF 34 DMRS WERE IDENTIFIED. GENES CONTAINING DMSS WITH THE TOP 5 HIGHEST BETA VALUE DIFFERENCES BETWEEN DR AND NON-DR PARTICIPANTS WERE LOCATED ON CHROMOSOME 1 AND WERE PRESENT IN THE S100A13 GENE, WHICH WAS ASSOCIATED WITH 71 GO TERMS. TWO S100A13 GENE SITES, I.E., CG02873163 AND CG11343894, DISPLAYED A GOOD CORRELATION WITH DR ON PYROSEQUENCING. CONCLUSIONS: DMSS IN THE S100A13 GENE MAY BE POTENTIAL BIOMARKERS OF DR. 2020 2 2079 43 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 3 1537 36 DNA METHYLATION IN ADOLESCENTS WITH ANXIETY DISORDER: A LONGITUDINAL STUDY. ANXIETY DISORDERS (AD) TYPICALLY MANIFEST IN CHILDREN AND ADOLESCENTS AND MIGHT PERSIST INTO ADULTHOOD. HOWEVER, THERE ARE STILL FEW DATA CONCERNING EPIGENETIC MECHANISMS ASSOCIATED WITH ONSET, PERSISTENCE OR REMISSION OF AD OVER TIME. WE INVESTIGATED A COHORT OF ADOLESCENTS AND YOUNG ADULTS AT BASELINE (AGE; 13.19 +/- 2.38) AND AFTER 5 YEARS AND CLASSIFIED THEM ACCORDING TO THE AD DIAGNOSIS AND THEIR LONGITUDINAL TRAJECTORIES INTO 4 GROUPS: (1) TYPICALLY DEVELOPING COMPARISONS (TDC; CONTROL GROUP, N = 14); (2) INCIDENT (AD IN THE SECOND EVALUATION ONLY, N = 11); (3) PERSISTENT (AD IN BOTH EVALUATIONS, N = 14) AND (4) REMITTENT (AD IN THE FIRST EVALUATION ONLY, N = 8). DNA METHYLATION WAS EVALUATED WITH THE INFINIUM HUMANMETHYLATION450 BEADCHIP FROM SALIVA SAMPLES COLLECTED AT BOTH EVALUATIONS. GENE SET ENRICHMENT ANALYSIS WAS APPLIED TO CONSIDER BIOLOGICAL PATHWAYS. WE FOUND DECREASED DNA METHYLATION IN TDC GROUP WHILE THE CHRONIC CASES OF AD PRESENTED HYPERMETHYLATION IN CENTRAL NERVOUS SYSTEM DEVELOPMENT PATHWAYS. MOREOVER, WE SHOWED THAT THIS PERSISTENT GROUP ALSO PRESENTED HYPERMETHYLATION WHILE THE OTHER THREE GROUPS WERE ASSOCIATED WITH HYPOMETHYLATION IN NERVOUS SYSTEM DEVELOPMENT PATHWAY. INCIDENCE AND REMISSION GROUPS WERE ASSOCIATED WITH INCREASED AND DECREASED METHYLATION IN NEURON DEVELOPMENT PATHWAYS, RESPECTIVELY. LARGER STUDIES ARE LIKELY TO DETECT SPECIFIC GENES RELEVANT TO AD. 2018 4 2418 42 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 5 1444 40 DIFFERENTIALLY HYPOMETHYLATED CELL-FREE DNA AND CORONARY COLLATERAL CIRCULATION. BACKGROUND: THE FACTORS AFFECTING CARDIOPROTECTIVE COLLATERAL CIRCULATION ARE STILL INCOMPLETELY UNDERSTOOD. RECENTLY, CHARACTERISTICS, SUCH AS CPG METHYLATION OF CELL-FREE DNA (CFDNA), HAVE BEEN REPORTED AS MARKERS WITH CLINICAL UTILITY. THE AIM OF THIS STUDY WAS TO EVALUATE WHETHER CFDNA METHYLATION PATTERNS ARE ASSOCIATED WITH THE GRADE OF CORONARY COLLATERAL CIRCULATION (CCC). RESULT: IN THIS CASE-CONTROL STUDY, CLINICAL AND ANGIOGRAPHIC DATA WERE OBTAINED FROM 143 PATIENTS (MEAN AGE, 58 YEARS, MALE 71%) WITH CHRONIC TOTAL CORONARY OCCLUSION. ENZYMATIC METHYL-SEQUENCING (EM-SEQ) LIBRARIES WERE PREPARED USING THE CFDNA EXTRACTED FROM THE PLASMA. DATA WERE PROCESSED TO OBTAIN THE AVERAGE METHYLATION FRACTION (AMF) TABLES OF GENOMIC REGIONS FROM WHICH BLACKLISTED REGIONS WERE REMOVED. UNSUPERVISED ANALYSIS OF THE OBTAINED AMF VALUES SHOWED THAT SOME OF THE CHANGES IN METHYLATION WERE DUE TO CCC. THROUGH RANDOM FOREST PREPARATION PROCESS, 256 DIFFERENTIALLY METHYLATED REGION (DMR) CANDIDATES SHOWING STRONG ASSOCIATION WITH CCC WERE SELECTED. A RANDOM FOREST CLASSIFIER WAS THEN CONSTRUCTED, AND THE AREA UNDER THE CURVE OF THE RECEIVER OPERATING CHARACTERISTIC CURVE INDICATED AN APPROPRIATE PREDICTIVE FUNCTION FOR CCC. FINALLY, 20 DMRS WERE IDENTIFIED TO HAVE SIGNIFICANTLY DIFFERENT AMF VALUES BETWEEN THE GOOD AND POOR CCC GROUPS. PARTICULARLY, THE GOOD CCC GROUP EXHIBITED HYPOMETHYLATED DMRS. PATHWAY ANALYSIS REVEALED FIVE PATHWAYS, INCLUDING TGF-BETA SIGNALING, TO BE ASSOCIATED WITH GOOD CCC. CONCLUSION: THESE DATA HAVE DEMONSTRATED THAT DIFFERENTIAL HYPOMETHYLATION WAS IDENTIFIED IN DOZENS OF CFDNA REGIONS IN PATIENTS WITH GOOD CCC. OUR RESULTS SUPPORT THE CLINICAL UTILITY OF NONINVASIVELY OBTAINED EPIGENETIC SIGNATURES FOR PREDICTING COLLATERAL CIRCULATION IN PATIENTS WITH VASCULAR DISEASES. 2022 6 3442 46 HYPERMETHYLATION IN THE PROMOTER OF THE MTHFR GENE IS ASSOCIATED WITH DIABETIC COMPLICATIONS AND BIOCHEMICAL INDICATORS. BACKGROUND: DNA METHYLATION IS AN EPIGENETIC MECHANISM FOR REGULATING THE TRANSCRIPTION OF MANY GENES AND HAS BEEN LINKED TO THE DEVELOPMENT OF VARIOUS DISEASES. A PROMISING GENE TO INVESTIGATE IS METHYLENETETRAHYDROFOLATE REDUCTASE (MTHFR), SINCE THE ENZYME METHYLENETETRAHYDROFOLATE REDUCTASE (MTHFR) PROMOTES METHYL RADICAL SYNTHESIS IN THE HOMOCYSTEINE CYCLE AND CAN PROVIDE METHYL GROUPS FOR DNA METHYLATION. IN ADDITION, SEVERAL STUDIES HAVE CORRELATED GENE POLYMORPHISMS OF THIS ENZYME WITH A GREATER RISK OF DIABETES, BUT LITTLE IS KNOWN REGARDING THE RELATIONSHIP BETWEEN EPIGENETIC CHANGES IN THIS GENE AND DIABETES AND ITS COMPLICATIONS. THE AIM OF THIS STUDY WAS TO INVESTIGATE THE RELATIONSHIP BETWEEN METHYLATION PROFILE IN THE MTHFR GENE PROMOTER AND BIOCHEMICAL, INFLAMMATORY AND OXIDATIVE STRESS MARKERS IN INDIVIDUALS WITH TYPE 2 DIABETES (T2DM) WHO HAVE BEEN DIAGNOSED FOR 5-10 YEARS WITH OR WITHOUT DIABETIC RETINOPATHY (DR) AND NEPHROPATHY (DN). METHODS: SPECIFIC PCR FOR METHYLATION (MSP) WAS USED TO ANALYZE MTHFR METHYLATION PROFILE IN LEUCOCYTES DNA. BIOCHEMICAL MARKERS (GLYCEMIA, GLYCATED HEMOGLOBIN, TOTAL CHOLESTEROL, LDL, HDL, TRIGLYCERIDES, SERUM CREATININE), INFLAMMATORY MARKERS (C-REACTIVE PROTEIN AND ALPHA-1 ACID GLYCOPROTEIN) AND OXIDATIVE STRESS (TOTAL ANTIOXIDANT AND MALONALDEHYDE) WERE DETERMINED IN PERIPHERIC BLOOD SAMPLES AND MICROALBUMINURIA IN 24 H URINE SAMPLES. THE X(2) AND MANN-WHITNEY STATISTICAL TESTS WERE PERFORMED AND P < 0.05 WERE CONSIDERED SIGNIFICANT. RESULTS: THE HYPERMETHYLATED PROFILE WAS MOST FREQUENTLY OBSERVED IN INDIVIDUALS WITH RETINOPATHY (P < 0.01) AND WAS ASSOCIATED WITH HIGHER TOTAL CHOLESTEROL AND LDL LEVELS (P = 0.0046, 0.0267, RESPECTIVELY). INDIVIDUALS WITH DN AND HYPERMETHYLATED PROFILES HAD HIGHER LEVELS OF ALPHA-1 ACID GLYCOPROTEIN (P = 0.0080) AND TOTAL ANTIOXIDANT CAPACITY (P = 0.0169) COMPARED TO SUBJECTS WITHOUT COMPLICATIONS. CONCLUSIONS: HYPERMETHYLATION IN THE PROMOTER OF THE MTHFR GENE IS ASSOCIATED WITH THE OCCURRENCE OF DR AND WITH BIOCHEMICAL, INFLAMMATORY AND OXIDATIVE STRESS PARAMETERS IN THE CONTEXT OF CHRONIC COMPLICATIONS. 2017 7 1345 33 DETECTION OF DIFFERENTIALLY METHYLATED REGIONS USING BAYES FACTOR FOR ORDINAL GROUP RESPONSES. RESEARCHERS IN GENOMICS ARE INCREASINGLY INTERESTED IN EPIGENETIC FACTORS SUCH AS DNA METHYLATION, BECAUSE THEY PLAY AN IMPORTANT ROLE IN REGULATING GENE EXPRESSION WITHOUT CHANGES IN THE DNA SEQUENCE. THERE HAVE BEEN SIGNIFICANT ADVANCES IN DEVELOPING STATISTICAL METHODS TO DETECT DIFFERENTIALLY METHYLATED REGIONS (DMRS) ASSOCIATED WITH BINARY DISEASE STATUS. MOST OF THESE METHODS ARE BEING DEVELOPED FOR DETECTING DIFFERENTIAL METHYLATION RATES BETWEEN CASES AND CONTROLS. WE CONSIDER MULTIPLE SEVERITY LEVELS OF DISEASE, AND DEVELOP A BAYESIAN STATISTICAL METHOD TO DETECT THE REGION WITH INCREASING (OR DECREASING) METHYLATION RATES AS THE DISEASE SEVERITY INCREASES. PATIENTS ARE CLASSIFIED INTO MORE THAN TWO GROUPS, BASED ON THE DISEASE SEVERITY (E.G., STAGES OF CANCER), AND DMRS ARE DETECTED BY USING MOVING WINDOWS ALONG THE GENOME. WITHIN EACH WINDOW, THE BAYES FACTOR IS CALCULATED TO TEST THE HYPOTHESIS OF MONOTONIC INCREASE IN METHYLATION RATES CORRESPONDING TO SEVERITY OF THE DISEASE VERSUS NO DIFFERENCE. A MIXED-EFFECT MODEL IS USED TO INCORPORATE THE CORRELATION OF METHYLATION RATES OF NEARBY CPG SITES IN THE REGION. RESULTS FROM EXTENSIVE SIMULATION INDICATE THAT OUR PROPOSED METHOD IS STATISTICALLY VALID AND REASONABLY POWERFUL. WE DEMONSTRATE OUR APPROACH ON A BISULFITE SEQUENCING DATASET FROM A CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) STUDY. 2019 8 6311 31 THE RELATION BETWEEN DNA METHYLATION PATTERNS AND SERUM CYTOKINE LEVELS IN COMMUNITY-DWELLING ADULTS: A PRELIMINARY STUDY. BACKGROUND: THE LEVELS OF CIRCULATING CYTOKINES FLUCTUATE WITH AGE, ACUTE ILLNESS, AND CHRONIC DISEASE, AND ARE PREDICTIVE OF MORTALITY; THIS IS ALSO TRUE FOR PATTERNS OF DNA (CPG) METHYLATION. GIVEN THAT IMMUNE CELLS ARE PARTICULARLY SENSITIVE TO CHANGES IN THE CONCENTRATION OF CYTOKINES IN THEIR MICROENVIRONMENT, WE HYPOTHESIZED THAT SERUM LEVELS OF TNF, IL-6, IL-8 AND IL-10 WOULD CORRELATE WITH GENOME-WIDE ALTERATIONS IN THE DNA METHYLATION LEVELS OF BLOOD LEUKOCYTES. TO TEST THIS, WE EVALUATED COMMUNITY-DWELLING ADULTS (N = 14; 48-78 YEARS OLD) RECRUITED TO A PILOT STUDY FOR THE CANADIAN LONGITUDINAL STUDY ON AGING (CLSA), EXAMINING DNA METHYLATION PATTERNS IN PERIPHERAL BLOOD MONONUCLEAR CELLS USING THE ILLUMINA HUMANMETHYLATION 450 K BEADCHIP. RESULTS: WE SHOW THAT, APART FROM AGE, SERUM IL-10 LEVELS EXHIBITED THE MOST SUBSTANTIAL ASSOCIATION TO DNA METHYLATION PATTERNS, FOLLOWED BY TNF, IL-6 AND IL-8. FURTHERMORE, WHILE THE LEVELS OF THESE CYTOKINES WERE HIGHER IN ELDERLY ADULTS, NO ASSOCIATIONS WITH EPIGENETIC ACCELERATED AGING, DERIVED USING THE EPIGENETIC CLOCK, WERE OBSERVED. CONCLUSIONS: AS A PRELIMINARY STUDY WITH A SMALL SAMPLE SIZE, THE CONCLUSIONS DRAWN FROM THIS WORK MUST BE VIEWED WITH CAUTION; HOWEVER, OUR OBSERVATIONS ARE ENCOURAGING AND CERTAINLY WARRANT MORE SUITABLY POWERED STUDIES OF THIS RELATIONSHIP. 2017 9 2633 42 EPIGENOME-WIDE DNA METHYLATION PATTERNS ASSOCIATED WITH FATIGUE IN PRIMARY SJOGREN'S SYNDROME. OBJECTIVE: CHRONIC FATIGUE IS A COMMON, DISABLING AND POORLY UNDERSTOOD PHENOMENON. RECENT STUDIES INDICATE THAT EPIGENETIC MECHANISMS MAY BE INVOLVED IN THE EXPRESSION OF FATIGUE, A PROMINENT FEATURE OF PRIMARY SS (PSS). THE AIM OF THIS STUDY WAS TO INVESTIGATE WHETHER DNA METHYLATION PROFILES OF WHOLE BLOOD ARE ASSOCIATED WITH FATIGUE IN PATIENTS WITH PSS. METHODS: FORTY-EIGHT PSS PATIENTS WITH HIGH (N = 24) OR LOW (N = 24) FATIGUE AS MEASURED BY A VISUAL ANALOGUE SCALE WERE INCLUDED. GENOME-WIDE DNA METHYLATION WAS INVESTIGATED USING THE ILLUMINA HUMANMETHYLATION450 BEADCHIP ARRAY. AFTER QUALITY CONTROL, A TOTAL OF 383 358 CYTOSINE-PHOSPHATE-GUANINE (CPG) SITES REMAINED FOR FURTHER ANALYSIS. AGE, SEX AND DIFFERENTIAL CELL COUNT ESTIMATES WERE INCLUDED AS COVARIATES IN THE ASSOCIATION MODEL. A FALSE DISCOVERY RATE-CORRECTED P < 0.05 WAS CONSIDERED SIGNIFICANT, AND A CUT-OFF OF 3% AVERAGE DIFFERENCE IN METHYLATION LEVELS BETWEEN HIGH- AND LOW-FATIGUE PATIENTS WAS APPLIED. RESULTS: A TOTAL OF 251 DIFFERENTIALLY METHYLATED CPG SITES WERE ASSOCIATED WITH FATIGUE. THE CPG SITE WITH THE MOST PRONOUNCED HYPOMETHYLATION IN PSS HIGH FATIGUE ANNOTATED TO THE SBF2-ANTISENSE RNA1 GENE. THE MOST DISTINCT HYPERMETHYLATION WAS OBSERVED AT A CPG SITE ANNOTATED TO THE LYMPHOTOXIN ALPHA GENE. FUNCTIONAL PATHWAY ANALYSIS OF GENES WITH DIFFERENTLY METHYLATED CPG SITES IN SUBJECTS WITH HIGH VS LOW FATIGUE REVEALED ENRICHMENT IN SEVERAL PATHWAYS ASSOCIATED WITH INNATE AND ADAPTIVE IMMUNITY. CONCLUSION: SOME GENES INVOLVED IN REGULATION OF THE IMMUNE SYSTEM AND IN INFLAMMATION ARE DIFFERENTLY METHYLATED IN PSS PATIENTS WITH HIGH VS LOW FATIGUE. THESE FINDINGS POINT TO FUNCTIONAL NETWORKS THAT MAY UNDERLIE FATIGUE. EPIGENETIC CHANGES COULD CONSTITUTE A FATIGUE-REGULATING MECHANISM IN PSS. 2016 10 1586 46 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 11 274 31 AGE-RELATED CHANGES IN DNA METHYLATION AFFECT RENAL HISTOLOGY AND POST-TRANSPLANT FIBROSIS. DURING AGEING, KIDNEY FUNCTION DECREASES DUE TO RENAL TUBULAR ATROPHY, INTERSTITIAL FIBROSIS, GLOMERULOSCLEROSIS AND ARTERIOSCLEROSIS. RECENTLY, CHANGES IN DNA METHYLATION WERE SHOWN TO CONTRIBUTE TO VARIOUS AGEING PROCESSES. HOWEVER, IT IS UNKNOWN WHETHER SUCH CHANGES ALSO CONTRIBUTE TO AGE-RELATED KIDNEY DYSFUNCTION. TO ASSESS THIS, WE PROFILED GENOME-WIDE CHANGES IN DNA METHYLATION (OVER 800 000 CPG SITES) IN 95 RENAL BIOPSIES OBTAINED PRIOR TO KIDNEY TRANSPLANTATION FROM DONORS AGED 16 TO 73 YEARS. DONOR AGE SIGNIFICANTLY ASSOCIATED WITH THE METHYLATION OF 92 778 CPGS (FALSE DISCOVERY RATE UNDER 0.05), CORRESPONDING TO 10 285 DIFFERENTIALLY METHYLATED REGIONS. THESE REGIONS WERE MOST FREQUENTLY LOCATED IN GENES INVOLVED IN THE WNT/BETA-CATENIN SIGNALING PATHWAY. USING AN INDEPENDENT COHORT OF 67 BIOPSIES, WE AUTONOMOUSLY VALIDATED THESE FINDINGS. INTERESTINGLY, THE METHYLATION STATUS OF THESE 92 778 AGE-RELATED CPGS WAS ASSOCIATED WITH GLOMERULOSCLEROSIS (34.4% OF CPGS AT A FALSE DISCOVERY RATE UNDER 0.05) AND INTERSTITIAL FIBROSIS (0.9%) AND GRAFT FUNCTION AT ONE YEAR AFTER TRANSPLANTATION, BUT NOT WITH TUBULAR ATROPHY AND ARTERIOSCLEROSIS. NO ASSOCIATION WAS OBSERVED WITH ANY OF THESE PATHOLOGIES AT THE TIME OF TRANSPLANTATION (0% AT A FALSE DISCOVERY RATE UNDER 0.05). THUS, AGE-ASSOCIATED CHANGES IN DNA METHYLATION AT THE TIME OF TRANSPLANTATION PREDICT FUTURE INJURY OF TRANSPLANTED KIDNEYS. SPECIFICALLY, OUR EPIGENOME-WIDE ASSOCIATION STUDY DEMONSTRATES THAT EPIGENETIC RENAL AGEING IS IMPLICATED IN PROGRESSIVE FIBROSIS IN BOTH THE GLOMERULUS AND THE INTERSTITIUM. 2019 12 1910 42 ENRICHMENT OF GENOMIC PATHWAYS BASED ON DIFFERENTIAL DNA METHYLATION PROFILES ASSOCIATED WITH KNEE OSTEOARTHRITIS PAIN. OUR STUDY AIMED TO IDENTIFY DIFFERENTIALLY METHYLATED REGIONS (I.E., GENOMIC REGION WHERE MULTIPLE ADJACENT CPG SITES SHOW DIFFERENTIAL METHYLATION) AND THEIR ENRICHED GENOMIC PATHWAYS ASSOCIATED WITH KNEE OSTEOARTHRITIS PAIN (KOA). WE RECRUITED COGNITIVELY HEALTHY MIDDLE TO OLDER AGED (AGE 45-85) ADULTS WITH (N = 182) AND WITHOUT (N = 31) SELF-REPORTED KOA PAIN. WE ALSO EXTRACTED DNA FROM PERIPHERAL BLOOD THAT WAS ANALYZED USING METHYLATIONEPIC ARRAYS. THE R PACKAGE MINFI (ARYEE ET AL., 2014) WAS USED TO PERFORM METHYLATION DATA PREPROCESSING AND QUALITY CONTROL. TO INVESTIGATE BIOLOGICAL PATHWAYS IMPACTED BY DIFFERENTIAL METHYLATION, WE PERFORMED PATHWAY ENRICHMENT ANALYSIS USING INGENUITY PATHWAY ANALYSIS (IPA) TO IDENTIFY CANONICAL PATHWAYS AND UPSTREAM REGULATORS. ANNOTATED GENES WITHIN +/- 5 KB OF THE PUTATIVE DIFFERENTIALLY METHYLATED REGIONS (DMRS, P < 0.05) WERE SUBJECTED TO THE IPA ANALYSIS. THERE WAS NO SIGNIFICANT DIFFERENCE IN AGE, SEX, STUDY SITE BETWEEN NO PAIN AND PAIN GROUP (P > 0.05). NON-HISPANIC BLACK INDIVIDUALS WERE OVERREPRESENTED IN THE PAIN GROUP (P = 0.003). AT RAW P < 0.05 CUTOFF, WE IDENTIFIED A TOTAL OF 19,710 CPG PROBES, INCLUDING 13,951 HYPERMETHYLATED CPG PROBES, FOR WHICH DNA METHYLATION LEVEL WAS HIGHER IN THE GROUPS WITH HIGHEST PAIN GRADES. WE ALSO IDENTIFIED 5,759 HYPOMETHYLATED CPG PROBES FOR WHICH DNA METHYLATION LEVEL WAS LOWER IN THE PAIN GROUPS WITH HIGHER PAIN GRADES. IPA REVEALED THAT PAIN-RELATED DMRS WERE ENRICHED ACROSS MULTIPLE PATHWAYS AND UPSTREAM REGULATORS. THE TOP 10 CANONICAL PATHWAYS WERE LINKED TO CELLULAR SIGNALING PROCESSES RELATED TO IMMUNE RESPONSES (I.E., ANTIGEN PRESENTATION, PD-1, PD-L1 CANCER IMMUNOTHERAPY, B CELL DEVELOPMENT, IL-4 SIGNALING, TH1 AND TH2 ACTIVATION PATHWAY, AND PHAGOSOME MATURATION). MOREOVER, IN TERMS OF UPSTREAM REGULATORS, NDUFAF3 WAS THE MOST SIGNIFICANT (P = 8.6E-04) UPSTREAM REGULATOR. OUR FINDINGS SUPPORT PREVIOUS PRELIMINARY WORK SUGGESTING THE IMPORTANCE OF EPIGENETIC REGULATION OF THE IMMUNE SYSTEM IN KNEE PAIN AND THE NEED FOR FUTURE WORK TO UNDERSTAND THE EPIGENETIC CONTRIBUTIONS TO CHRONIC PAIN. 2022 13 972 38 CHRONIC OBSTRUCTIVE PULMONARY DISEASE IS ASSOCIATED WITH EPIGENOME-WIDE DIFFERENTIAL METHYLATION IN BAL LUNG CELLS. DNA METHYLATION PATTERNS IN CHRONIC PULMONARY OBSTRUCTIVE DISEASE (COPD) MIGHT OFFER NEW INSIGHTS INTO DISEASE PATHOGENESIS. TO ASSESS METHYLATION PROFILES IN THE MAIN COPD TARGET ORGAN, WE PERFORMED AN EPIGENOME-WIDE ASSOCIATION STUDY ON BAL CELLS. BRONCHOSCOPIES WERE PERFORMED IN 18 SUBJECTS WITH COPD AND 15 CONTROL SUBJECTS (EX- AND CURRENT SMOKERS). DNA METHYLATION WAS MEASURED USING THE ILLUMINA METHYLATIONEPIC BEADCHIP KIT, COVERING MORE THAN 850,000 CPGS. DIFFERENTIALLY METHYLATED POSITIONS (DMPS) WERE EXAMINED FOR 1) ENRICHMENT IN PATHWAYS AND FUNCTIONAL GENE RELATIONSHIPS USING THE KYOTO ENCYCLOPEDIA OF GENES AND GENOMES AND GENE ONTOLOGY, 2) ACCELERATED AGING USING HORVATH'S EPIGENETIC CLOCK, 3) CORRELATION WITH GENE EXPRESSION, AND 4) COLOCALIZATION WITH GENETIC VARIATION. WE FOUND 1,155 BONFERRONI-SIGNIFICANT (P < 6.74 X 10(-8)) DMPS ASSOCIATED WITH COPD, MANY WITH LARGE EFFECT SIZES. FUNCTIONAL ANALYSIS IDENTIFIED BIOLOGICALLY PLAUSIBLE PATHWAYS AND GENE RELATIONSHIPS, INCLUDING ENRICHMENT FOR TRANSCRIPTION FACTOR ACTIVITY. STRONG CORRELATION WAS FOUND BETWEEN DNA METHYLATION AND CHRONOLOGICAL AGE BUT NOT BETWEEN COPD AND ACCELERATED AGING. FOR 79 UNIQUE DMPS, DNA METHYLATION CORRELATED SIGNIFICANTLY WITH GENE EXPRESSION IN BAL CELLS. THIRTY-NINE PERCENT OF DMPS WERE COLOCALIZED WITH COPD-ASSOCIATED SNPS. TO THE BEST OF OUR KNOWLEDGE, THIS IS THE FIRST EPIGENOME-WIDE ASSOCIATION STUDY OF COPD ON BAL CELLS, AND OUR ANALYSES REVEALED MANY DIFFERENTIAL METHYLATION SITES. INTEGRATION WITH MRNA DATA SHOWED A STRONG FUNCTIONAL READOUT FOR RELEVANT GENES, IDENTIFYING SITES WHERE DNA METHYLATION MIGHT DIRECTLY AFFECT EXPRESSION. ALMOST HALF OF DMPS WERE COLOCATED WITH SNPS IDENTIFIED IN PREVIOUS GENOME-WIDE ASSOCIATION STUDIES OF COPD, SUGGESTING JOINT GENETIC AND EPIGENETIC PATHWAYS RELATED TO DISEASE. 2022 14 1493 39 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 15 3652 38 INDIVIDUAL DNA METHYLATION PATTERN SHIFTS IN NANOPARTICLES-EXPOSED WORKERS ANALYZED IN FOUR CONSECUTIVE YEARS. A DNA METHYLATION PATTERN REPRESENTS AN ORIGINAL PLAN OF THE FUNCTION SETTINGS OF INDIVIDUAL CELLS AND TISSUES. THE BASIC STRATEGIES OF ITS DEVELOPMENT AND CHANGES DURING THE HUMAN LIFETIME ARE KNOWN, BUT THE DETAILS RELATED TO ITS MODIFICATION OVER THE YEARS ON AN INDIVIDUAL BASIS HAVE NOT YET BEEN STUDIED. MOREOVER, CURRENT EVIDENCE SHOWS THAT ENVIRONMENTAL EXPOSURE COULD GENERATE CHANGES IN DNA METHYLATION SETTINGS AND, SUBSEQUENTLY, THE FUNCTION OF GENES. IN THIS STUDY, WE ANALYZED THE EFFECT OF CHRONIC EXPOSURE TO NANOPARTICLES (NP) IN OCCUPATIONALLY EXPOSED WORKERS REPEATEDLY SAMPLED IN FOUR CONSECUTIVE YEARS (2016-2019). A DETAILED METHYLATION PATTERN ANALYSIS OF 14 PERSONS (10 EXPOSED AND 4 CONTROLS) WAS PERFORMED ON AN INDIVIDUAL BASIS. A MICROARRAY-BASED APPROACH USING CHIPS, ALLOWING THE ASSESSMENT OF MORE THAN 850 K CPG LOCI, WAS USED. INDIVIDUAL DNA METHYLATION PATTERNS WERE COMPARED BY PRINCIPAL COMPONENT ANALYSIS (PCA). THE RESULTS SHOW THE SHIFT IN DNA METHYLATION PATTERNS IN INDIVIDUAL YEARS IN ALL THE EXPOSED AND CONTROL SUBJECTS. THE OVERALL RANGE OF DIFFERENCES VARIED BETWEEN THE YEARS IN INDIVIDUAL PERSONS. THE DIFFERENCES BETWEEN THE FIRST AND LAST YEAR OF EXAMINATION (A THREE-YEAR TIME PERIOD) SEEM TO BE CONSISTENTLY GREATER IN THE NP-EXPOSED SUBJECTS IN COMPARISON WITH THE CONTROLS. THE SELECTED 14 MOST DIFFERENTLY METHYLATED CG LOCI WERE RELATIVELY STABLE IN THE CHRONICALLY EXPOSED SUBJECTS. IN SUMMARY, THE SPECIFIC TYPE OF LONG-TERM EXPOSURE CAN CONTRIBUTE TO THE FIXING OF RELEVANT EPIGENETIC CHANGES RELATED TO A SPECIFIC ENVIRONMENT AS, E.G., NP INHALATION. 2021 16 1739 43 EARLY DNA METHYLATION CHANGES IN CHILDREN DEVELOPING BETA CELL AUTOIMMUNITY AT A YOUNG AGE. AIMS/HYPOTHESIS: TYPE 1 DIABETES IS A CHRONIC AUTOIMMUNE DISEASE OF COMPLEX AETIOLOGY, INCLUDING A POTENTIAL ROLE FOR EPIGENETIC REGULATION. PREVIOUS EPIGENOMIC STUDIES FOCUSED MAINLY ON CLINICALLY DIAGNOSED INDIVIDUALS. THE AIM OF THE STUDY WAS TO ASSESS EARLY DNA METHYLATION CHANGES ASSOCIATED WITH TYPE 1 DIABETES ALREADY BEFORE THE DIAGNOSIS OR EVEN BEFORE THE APPEARANCE OF AUTOANTIBODIES. METHODS: REDUCED REPRESENTATION BISULPHITE SEQUENCING (RRBS) WAS APPLIED TO STUDY DNA METHYLATION IN PURIFIED CD4(+) T CELL, CD8(+) T CELL AND CD4(-)CD8(-) CELL FRACTIONS OF 226 PERIPHERAL BLOOD MONONUCLEAR CELL SAMPLES LONGITUDINALLY COLLECTED FROM SEVEN TYPE 1 DIABETES-SPECIFIC AUTOANTIBODY-POSITIVE INDIVIDUALS AND CONTROL INDIVIDUALS MATCHED FOR AGE, SEX, HLA RISK AND PLACE OF BIRTH. WE ALSO EXPLORED CORRELATIONS BETWEEN DNA METHYLATION AND GENE EXPRESSION USING RNA SEQUENCING DATA FROM THE SAME SAMPLES. TECHNICAL VALIDATION OF RRBS RESULTS WAS PERFORMED USING PYROSEQUENCING. RESULTS: WE IDENTIFIED 79, 56 AND 45 DIFFERENTIALLY METHYLATED REGIONS IN CD4(+) T CELLS, CD8(+) T CELLS AND CD4(-)CD8(-) CELL FRACTIONS, RESPECTIVELY, BETWEEN TYPE 1 DIABETES-SPECIFIC AUTOANTIBODY-POSITIVE INDIVIDUALS AND CONTROL PARTICIPANTS. THE ANALYSIS OF PRE-SEROCONVERSION SAMPLES IDENTIFIED DNA METHYLATION SIGNATURES AT THE VERY EARLY STAGE OF DISEASE, INCLUDING DIFFERENTIAL METHYLATION AT THE PROMOTER OF IRF5 IN CD4(+) T CELLS. FURTHER, WE VALIDATED RRBS RESULTS USING PYROSEQUENCING AT THE FOLLOWING CPG SITES: CHR19:18118304 IN THE PROMOTER OF ARRDC2; CHR21:47307815 IN THE INTRON OF PCBP3; AND CHR14:81128398 IN THE INTERGENIC REGION NEAR TRAF3 IN CD4(+) T CELLS. CONCLUSIONS/INTERPRETATION: THESE PRELIMINARY RESULTS PROVIDE NOVEL INSIGHTS INTO CELL TYPE-SPECIFIC DIFFERENTIAL EPIGENETIC REGULATION OF GENES, WHICH MAY CONTRIBUTE TO TYPE 1 DIABETES PATHOGENESIS AT THE VERY EARLY STAGE OF DISEASE DEVELOPMENT. SHOULD THESE FINDINGS BE VALIDATED, THEY MAY SERVE AS A POTENTIAL SIGNATURE USEFUL FOR DISEASE PREDICTION AND MANAGEMENT. 2022 17 382 44 AN EPIGENOME-WIDE STUDY OF BODY MASS INDEX AND DNA METHYLATION IN BLOOD USING PARTICIPANTS FROM THE SISTER STUDY COHORT. BACKGROUND/OBJECTIVES: THE RELATIONSHIP BETWEEN OBESITY AND CHRONIC DISEASE RISK IS WELL-ESTABLISHED; THE UNDERLYING BIOLOGICAL MECHANISMS DRIVING THIS RISK INCREASE MAY INCLUDE OBESITY-RELATED EPIGENETIC MODIFICATIONS. TO EXPLORE THIS HYPOTHESIS, WE CONDUCTED A GENOME-WIDE ANALYSIS OF DNA METHYLATION AND BODY MASS INDEX (BMI) USING DATA FROM A SUBSET OF WOMEN IN THE SISTER STUDY. SUBJECTS/METHODS: THE SISTER STUDY IS A COHORT OF 50 884 US WOMEN WHO HAD A SISTER WITH BREAST CANCER BUT WERE FREE OF BREAST CANCER THEMSELVES AT ENROLLMENT. STUDY PARTICIPANTS COMPLETED EXAMINATIONS WHICH INCLUDED MEASUREMENTS OF HEIGHT AND WEIGHT, AND PROVIDED BLOOD SAMPLES. BLOOD DNA METHYLATION DATA GENERATED WITH THE ILLUMINA INFINIUM HUMANMETHYLATION27 BEADCHIP ARRAY COVERING 27,589 CPG SITES WAS AVAILABLE FOR 871 WOMEN FROM A PRIOR STUDY OF BREAST CANCER AND DNA METHYLATION. TO IDENTIFY DIFFERENTIALLY METHYLATED CPG SITES ASSOCIATED WITH BMI, WE ANALYZED THIS METHYLATION DATA USING ROBUST LINEAR REGRESSION WITH ADJUSTMENT FOR AGE AND CASE STATUS. FOR THOSE CPGS PASSING THE FALSE DISCOVERY RATE SIGNIFICANCE LEVEL, WE EXAMINED THE ASSOCIATION IN A REPLICATION SET COMPRISED OF A NON-OVERLAPPING GROUP OF 187 WOMEN FROM THE SISTER STUDY WHO HAD DNA METHYLATION DATA GENERATED USING THE INFINIUM HUMANMETHYLATION450 BEADCHIP ARRAY. ANALYSIS OF THIS EXPANDED 450 K ARRAY IDENTIFIED ADDITIONAL BMI-ASSOCIATED SITES WHICH WERE INVESTIGATED WITH TARGETED PYROSEQUENCING. RESULTS: FOUR CPG SITES REACHED GENOME-WIDE SIGNIFICANCE (FALSE DISCOVERY RATE (FDR) Q<0.05) IN THE DISCOVERY SET AND ASSOCIATIONS FOR ALL FOUR WERE SIGNIFICANT AT STRICT BONFERRONI CORRECTION IN THE REPLICATION SET. AN ADDITIONAL 23 SITES PASSED FDR IN THE REPLICATION SET AND FIVE WERE REPLICATED BY PYROSEQUENCING IN THE DISCOVERY SET. SEVERAL OF THE GENES IDENTIFIED INCLUDING ANGPT4, RORC, SOCS3, FSD2, XYLT1, ABCG1, STK39, ASB2 AND CRHR2 HAVE BEEN LINKED TO OBESITY AND OBESITY-RELATED CHRONIC DISEASES. CONCLUSIONS: OUR FINDINGS SUPPORT THE HYPOTHESIS THAT OBESITY-RELATED EPIGENETIC DIFFERENCES ARE DETECTABLE IN BLOOD AND MAY BE RELATED TO RISK OF CHRONIC DISEASE. 2017 18 6083 39 THE EFFECT OF SMOKING ON DNA METHYLATION OF PERIPHERAL BLOOD MONONUCLEAR CELLS FROM AFRICAN AMERICAN WOMEN. BACKGROUND: REGULAR SMOKING IS ASSOCIATED WITH A WIDE VARIETY OF SYNDROMES WITH PROMINENT INFLAMMATORY COMPONENTS SUCH AS CANCER, OBESITY AND TYPE 2 DIABETES. HEAVY REGULAR SMOKING IS ALSO ASSOCIATED WITH CHANGES IN THE DNA METHYLATION OF PERIPHERAL MONONUCLEAR CELLS. HOWEVER, IN YOUNGER SMOKERS, INFLAMMATORY EPIGENETIC FINDINGS ARE LARGELY ABSENT WHICH SUGGESTS THE INFLAMMATORY RESPONSE(S) TO SMOKING MAY BE DOSE DEPENDENT. TO HELP UNDERSTAND WHETHER PERIPHERAL MONONUCLEAR CELLS HAVE A ROLE IN MEDIATING THESE RESPONSES IN OLDER SMOKERS WITH HIGHER CUMULATIVE SMOKE EXPOSURE, WE EXAMINED GENOME-WIDE DNA METHYLATION IN A GROUP OF WELL CHARACTERIZED ADULT AFRICAN AMERICAN SUBJECTS INFORMATIVE FOR SMOKING, AS WELL AS SERUM C-REACTIVE PROTEIN (CRP) AND INTERLEUKIN-6 RECEPTOR (IL6R) LEVELS. IN ADDITION, COMPLEMENTARY BIOINFORMATIC ANALYSES WERE CONDUCTED TO DELINEATE POSSIBLE PATHWAYS AFFECTED BY LONG-TERM SMOKING. RESULTS: GENOME-WIDE DNA METHYLATION ANALYSIS WITH RESPECT TO SMOKING STATUS YIELDED 910 SIGNIFICANT LOCI AFTER BENJAMINI-HOCHBERG CORRECTION. IN PARTICULAR, TWO LOCI FROM THE AHRR GENE (CG05575921 AND CG23576855) AND ONE LOCUS FROM THE GPR15 GENE (CG19859270) WERE IDENTIFIED AS HIGHLY SIGNIFICANTLY DIFFERENTIALLY METHYLATED BETWEEN SMOKERS AND NON-SMOKERS. THE BIOINFORMATIC ANALYSES SHOWED THAT LONG-TERM CHRONIC SMOKING IS ASSOCIATED WITH ALTERED PROMOTER DNA METHYLATION OF GENES CODING FOR PROTEINS MAPPING TO CRITICAL SUB-NETWORKS MODERATING INFLAMMATION, IMMUNE FUNCTION, AND COAGULATION. CONCLUSIONS: WE CONCLUDE THAT CHRONIC REGULAR SMOKING IS ASSOCIATED WITH CHANGES IN PERIPHERAL MONONUCLEAR CELL METHYLATION SIGNATURE WHICH PERTURB INFLAMMATORY AND IMMUNE FUNCTION PATHWAYS AND MAY CONTRIBUTE TO INCREASED VULNERABILITY FOR COMPLEX ILLNESSES WITH INFLAMMATORY COMPONENTS. 2014 19 561 49 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 20 1519 36 DNA METHYLATION AT ATP11A CG11702988 IS A BIOMARKER OF LUNG DISEASE SEVERITY IN CYSTIC FIBROSIS: A LONGITUDINAL STUDY. CYSTIC FIBROSIS (CF) IS A CHRONIC GENETIC DISEASE THAT MAINLY AFFECTS THE RESPIRATORY AND GASTROINTESTINAL SYSTEMS. NO CURATIVE TREATMENTS ARE AVAILABLE, BUT THE FOLLOW-UP IN SPECIALIZED CENTERS HAS GREATLY IMPROVED THE PATIENT LIFE EXPECTANCY. ROBUST BIOMARKERS ARE REQUIRED TO MONITOR THE DISEASE, GUIDE TREATMENTS, STRATIFY PATIENTS, AND PROVIDE OUTCOME MEASURES IN CLINICAL TRIALS. IN THE PRESENT STUDY, WE OUTLINE A STRATEGY TO SELECT PUTATIVE DNA METHYLATION BIOMARKERS OF LUNG DISEASE SEVERITY IN CYSTIC FIBROSIS PATIENTS. IN THE DISCOVERY STEP, WE SELECTED SEVEN POTENTIAL BIOMARKERS USING A GENOME-WIDE DNA METHYLATION DATASET THAT WE GENERATED IN NASAL EPITHELIAL SAMPLES FROM THE METHYLCF COHORT. IN THE REPLICATION STEP, WE ASSESSED THE SAME BIOMARKERS USING SPUTUM CELL SAMPLES FROM THE METHYLBIOMARK COHORT. OF INTEREST, DNA METHYLATION AT THE CG11702988 SITE (ATP11A GENE) POSITIVELY CORRELATED WITH LUNG FUNCTION AND BMI, AND NEGATIVELY CORRELATED WITH LUNG DISEASE SEVERITY, P. AERUGINOSA CHRONIC INFECTION, AND THE NUMBER OF EXACERBATIONS. THESE RESULTS WERE REPLICATED IN PROSPECTIVE SPUTUM SAMPLES COLLECTED AT FOUR TIME POINTS WITHIN AN 18-MONTH PERIOD AND LONGITUDINALLY. TO CONCLUDE, (I) WE IDENTIFIED A DNA METHYLATION BIOMARKER THAT CORRELATES WITH CF SEVERITY, (II) WE PROVIDED A METHOD TO EASILY ASSESS THIS BIOMARKER, AND (III) WE CARRIED OUT THE FIRST LONGITUDINAL ANALYSIS OF DNA METHYLATION IN CF PATIENTS. THIS NEW EPIGENETIC BIOMARKER COULD BE USED TO STRATIFY CF PATIENTS IN CLINICAL TRIALS. 2021