1 3073 190 GENOME-WIDE DNA METHYLATION STATUS OF MONGOLIANS EXHIBITS SIGNS OF CELLULAR STRESS RESPONSE RELATED TO THEIR NOMADIC LIFESTYLE. BACKGROUND: EPIGENETICS IS CRUCIAL FOR CONNECTING ENVIRONMENTAL STRESSES WITH PHYSIOLOGICAL RESPONSES IN HUMANS. MONGOLIA, WHERE NOMADIC LIVESTOCK PASTORALISM HAS BEEN THE PRIMAL LIVELIHOOD, HAS A HIGHER PREVALENCE OF VARIOUS CHRONIC DISEASES THAN THE SURROUNDING EAST ASIAN REGIONS, WHICH ARE MORE SUITABLE FOR CROP FARMING. THE GENES RELATED TO DIETARY STRESS AND PATHOGENESIS OF RELATED DISORDERS MAY HAVE VARYING EPIGENETIC STATUSES AMONG THE HUMAN POPULATIONS WITH DIVERSE DIETARY CULTURES. HENCE, TO UNDERSTAND SUCH EPIGENETIC DIFFERENCES, WE CONDUCTED A COMPARATIVE ANALYSIS OF GENOME-WIDE DNA METHYLATION OF MONGOLIANS AND CROP-FARMING EAST ASIANS. METHODS: GENOME-WIDE DNA METHYLATION STATUS OF PERIPHERAL BLOOD CELLS (PBCS) FROM 23 MONGOLIAN ADULTS AND 24 THAI ADULTS WAS DETERMINED USING THE INFINIUM HUMAN METHYLATION 450K ARRAYS AND ANALYZED IN COMBINATION WITH PREVIOUSLY PUBLISHED 450K DATA OF 20 JAPANESE AND 8 CHINESE ADULTS. CPG SITES/REGIONS DIFFERENTIALLY METHYLATED BETWEEN MONGOLIANS AND CROP-FARMING EAST ASIANS WERE DETECTED USING A LINEAR MODEL ADJUSTED FOR SEX, AGE, ETHNICITY, AND IMMUNE CELL HETEROGENEITY ON RNBEADS SOFTWARE. RESULTS: OF THE QUALITY-CONTROLLED 389,454 AUTOSOMAL CPG SITES, 223 CPG SITES WERE SIGNIFICANTLY DIFFERENTIALLY METHYLATED AMONG MONGOLIANS AND THE FOUR CROP FARMING EAST ASIAN POPULATIONS (FALSE DISCOVERY RATE < 0.05). ANALYSES FOCUSED ON GENE PROMOTER REGIONS REVEALED THAT PM20D1 (PEPTIDASE M20 DOMAIN CONTAINING 1), WHICH IS INVOLVED IN MITOCHONDRIAL UNCOUPLING AND VARIOUS PROCESSES, INCLUDING CELLULAR PROTECTION FROM REACTIVE OXYGEN SPECIES (ROS) AND THERMOGENESIS, WAS THE TOP DIFFERENTIALLY METHYLATED GENE. MOREOVER, GENE ONTOLOGY ENRICHMENT ANALYSIS REVEALED THAT BIOLOGICAL PROCESSES RELATED TO ROS METABOLISM WERE OVERREPRESENTED AMONG THE TOP 1% DIFFERENTIALLY METHYLATED GENES. THE PROMOTER REGIONS OF THESE GENES WERE GENERALLY HYPERMETHYLATED IN MONGOLIANS, SUGGESTING THAT THE METABOLIC PATHWAY DETOXIFYING ROS MIGHT BE GLOBALLY SUPPRESSED IN MONGOLIANS, RESULTING IN THE HIGH SUSCEPTIBILITY OF THIS POPULATION TO VARIOUS CHRONIC DISEASES. CONCLUSIONS: THIS STUDY SHOWED A SIGNIFICANTLY DIVERSE DNA METHYLATION STATUS AMONG MONGOLIANS AND CROP-FARMING EAST ASIANS. FURTHER, WE FOUND AN ASSOCIATION BETWEEN THE DIFFERENTIALLY METHYLATED GENES AND VARIOUS METABOLIC AND NEURODEGENERATIVE DISEASES. KNOWLEDGE OF THE EPIGENETIC REGULATORS MIGHT HELP IN PROPER UNDERSTANDING, TREATMENT, AND CONTROL OF SUCH DISORDERS, AND PHYSIOLOGICAL ADAPTATION IN THE FUTURE. 2022 2 1529 48 DNA METHYLATION CHANGES IN WHOLE BLOOD AND CD16+ NEUTROPHILS IN RESPONSE TO CHRONIC FOLIC ACID SUPPLEMENTATION IN WOMEN OF CHILDBEARING AGE. FOLATE, A WATER-SOLUBLE VITAMIN, IS A KEY SOURCE OF ONE-CARBON GROUPS FOR DNA METHYLATION, BUT STUDIES OF THE DNA METHYLATION RESPONSE TO SUPPLEMENTAL FOLIC ACID YIELD INCONSISTENT RESULTS. THESE STUDIES ARE COMMONLY CONDUCTED USING WHOLE BLOOD, WHICH CONTAINS A MIXED POPULATION OF WHITE BLOOD CELLS THAT HAVE BEEN SHOWN TO CONFOUND RESULTS. THE OBJECTIVE OF THIS STUDY WAS TO DETERMINE IF CD16+ NEUTROPHILS MAY PROVIDE MORE SPECIFIC DATA THAN WHOLE BLOOD FOR IDENTIFYING DNA METHYLATION RESPONSE TO CHRONIC FOLIC ACID SUPPLEMENTATION. THE STUDY WAS PERFORMED IN NORMAL WEIGHT (BMI 18.5 - 24.9 KG/M2) WOMEN (18 - 35 Y; N = 12), WITH BLOOD SAMPLES TAKEN BEFORE AND AFTER 8 WEEKS OF FOLIC ACID SUPPLEMENTATION AT 800 MUG/DAY. DNA METHYLATION PATTERNS FROM WHOLE BLOOD AND ISOLATED CD16+ NEUTROPHILS WERE MEASURED ACROSS >485,000 CPG SITES THROUGHOUT THE GENOME USING THE INFINIUM HUMANMETHYLATION450 BEADCHIP. OVER THE COURSE OF THE 8-WEEK SUPPLEMENTATION, 6746 AND 7513 CPG SITES CHANGED (P < 0.05) IN WHOLE BLOOD AND CD16+ NEUTROPHILS, RESPECTIVELY. DNA METHYLATION DECREASED IN 68.4% (WHOLE BLOOD) AND 71.8% (CD16+ NEUTROPHILS) OF THESE SITES. THERE WERE ONLY 182 CPG SITES THAT CHANGED IN BOTH THE WHOLE BLOOD AND CD16+ NEUTROPHILS, 139 OF WHICH CHANGED IN THE SAME DIRECTION. THESE RESULTS SUGGEST THAT THE GENOME-WIDE DNA METHYLATION RESPONSE TO CHRONIC FOLIC ACID SUPPLEMENTATION IS DIFFERENT BETWEEN WHOLE BLOOD AND CD16+ NEUTROPHILS AND THAT A SINGLE WHITE BLOOD CELL TYPE MAY FUNCTION AS A MORE SPECIFIC EPIGENETIC REPORTER OF FOLATE STATUS THAN WHOLE BLOOD. 2017 3 1598 40 DNA METHYLATION SIGNATURE IN MONONUCLEAR CELLS AND PROINFLAMMATORY CYTOKINES MAY DEFINE MOLECULAR SUBTYPES IN SPORADIC MENIERE DISEASE. MENIERE DISEASE (MD) IS A MULTIFACTORIAL DISORDER OF THE INNER EAR CHARACTERIZED BY VERTIGO ATTACKS ASSOCIATED WITH SENSORINEURAL HEARING LOSS AND TINNITUS WITH A SIGNIFICANT HERITABILITY. ALTHOUGH MD HAS BEEN ASSOCIATED WITH SEVERAL GENES, NO EPIGENETIC STUDIES HAVE BEEN PERFORMED ON MD. HERE WE PERFORMED WHOLE-GENOME BISULFITE SEQUENCING IN 14 MD PATIENTS AND SIX HEALTHY CONTROLS, WITH THE AIM OF IDENTIFYING AN MD METHYLATION SIGNATURE AND POTENTIAL DISEASE MECHANISMS. WE OBSERVED A HIGH NUMBER OF DIFFERENTIALLY METHYLATED CPGS (DMC) WHEN COMPARING MD PATIENTS TO CONTROLS (N= 9545), SEVERAL OF THEM IN HEARING LOSS GENES, SUCH AS PCDH15,&NBSP;ADGRV1 AND CDH23. BIOINFORMATIC ANALYSES OF DMCS AND CIS-REGULATORY REGIONS PREDICTED PHENOTYPES RELATED TO ABNORMAL EXCITATORY POSTSYNAPTIC CURRENTS, ABNORMAL NMDA-MEDIATED RECEPTOR CURRENTS AND ABNORMAL GLUTAMATE-MEDIATED RECEPTOR CURRENTS WHEN COMPARING MD TO CONTROLS. MOREOVER, WE IDENTIFIED VARIOUS DMCS IN GENES PREVIOUSLY ASSOCIATED WITH COCHLEOVESTIBULAR PHENOTYPES IN MICE. WE HAVE ALSO FOUND 12 UNDERMETHYLATED REGIONS (UMR) THAT WERE EXCLUSIVE TO MD, INCLUDING TWO UMR IN AN INTER CPG ISLAND IN THE PHB GENE. WE SUGGEST THAT THE DNA METHYLATION SIGNATURE ALLOWS DISTINGUISHING BETWEEN MD PATIENTS AND CONTROLS. THE ENRICHMENT ANALYSIS CONFIRMS PREVIOUS FINDINGS OF A CHRONIC INFLAMMATORY PROCESS UNDERLYING MD. 2021 4 1541 38 DNA METHYLATION IN GENES OF LONGEVITY-REGULATING PATHWAYS: ASSOCIATION WITH OBESITY AND METABOLIC COMPLICATIONS. AGING IS THE MAIN RISK FACTOR FOR MOST CHRONIC DISEASES. EPIGENETIC MECHANISMS, SUCH AS DNA METHYLATION (DNAM) PLAYS A PIVOTAL ROLE IN THE REGULATION OF PHYSIOLOGICAL RESPONSES THAT CAN VARY ALONG LIFESPAN. THE AIM OF THIS RESEARCH WAS TO ANALYZE THE ASSOCIATION BETWEEN LEUKOCYTE DNAM IN GENES INVOLVED IN LONGEVITY AND THE OCCURRENCE OF OBESITY AND RELATED METABOLIC ALTERATIONS IN AN ADULT POPULATION. SUBJECTS FROM THE MENA COHORT (N=474) WERE CATEGORIZED ACCORDING TO AGE (<45 VS 45>) AND THE PRESENCE OF METABOLIC ALTERATIONS: INCREASED WAIST CIRCUMFERENCE, HYPERCHOLESTEROLEMIA, INSULIN RESISTANCE, AND METABOLIC SYNDROME. THE METHYLATION LEVELS OF 58 CPG SITES LOCATED AT GENES INVOLVED IN LONGEVITY-REGULATING PATHWAYS WERE STRONGLY CORRELATED (FDR-ADJUSTED< 0.0001) WITH BMI. FIFTEEN OF THEM WERE DIFFERENTIALLY METHYLATED (P<0.05) BETWEEN YOUNGER AND OLDER SUBJECTS THAT EXHIBITED AT LEAST ONE METABOLIC ALTERATION. SIX OF THESE CPG SITES, LOCATED AT MTOR (CG08862778), ULK1 (CG07199894), ADCY6 (CG11658986), IGF1R (CG01284192), CREB5 (CG11301281), AND RELA (CG08128650), WERE COMMON TO THE METABOLIC TRAITS, AND CREB5, RELA, AND ULK1 WERE STATISTICALLY ASSOCIATED WITH AGE. IN SUMMARY, LEUKOCYTE DNAM LEVELS OF SEVERAL CPG SITES LOCATED AT GENES INVOLVED IN LONGEVITY-REGULATING PATHWAYS WERE ASSOCIATED WITH OBESITY AND METABOLIC SYNDROME TRAITS, SUGGESTING A ROLE OF DNAM IN AGING-RELATED METABOLIC ALTERATIONS. 2019 5 1990 42 EPIGENETIC ANALYSIS OF PAGET'S DISEASE OF BONE IDENTIFIES DIFFERENTIALLY METHYLATED LOCI THAT PREDICT DISEASE STATUS. PAGET'S DISEASE OF BONE (PDB) IS CHARACTERIZED BY FOCAL INCREASES IN DISORGANIZED BONE REMODELING. THIS STUDY AIMS TO CHARACTERIZE PDB-ASSOCIATED CHANGES IN DNA METHYLATION PROFILES IN PATIENTS' BLOOD. META-ANALYSIS OF DATA FROM THE DISCOVERY AND CROSS-VALIDATION SET, EACH COMPRISING 116 PDB CASES AND 130 CONTROLS, REVEALED SIGNIFICANT DIFFERENCES IN DNA METHYLATION AT 14 CPG SITES, 4 CPG ISLANDS, AND 6 GENE-BODY REGIONS. THESE LOCI, INCLUDING TWO CHARACTERIZED AS FUNCTIONAL THROUGH EXPRESSION QUANTITATIVE TRAIT-METHYLATION ANALYSIS, WERE ASSOCIATED WITH FUNCTIONS RELATED TO OSTEOCLAST DIFFERENTIATION, MECHANICAL LOADING, IMMUNE FUNCTION, AND VIRAL INFECTION. A MULTIVARIATE CLASSIFIER BASED ON DISCOVERY SAMPLES WAS FOUND TO DISCRIMINATE PDB CASES AND CONTROLS FROM THE CROSS-VALIDATION WITH A SENSITIVITY OF 0.84, SPECIFICITY OF 0.81, AND AN AREA UNDER CURVE OF 92.8%. IN CONCLUSION, THIS STUDY HAS SHOWN FOR THE FIRST TIME THAT EPIGENETIC FACTORS CONTRIBUTE TO THE PATHOGENESIS OF PDB AND MAY OFFER DIAGNOSTIC MARKERS FOR PREDICTION OF THE DISEASE. 2021 6 6190 50 THE IMPACT OF METHYLATION QUANTITATIVE TRAIT LOCI (MQTLS) ON ACTIVE SMOKING-RELATED DNA METHYLATION CHANGES. BACKGROUND: METHYLATION QUANTITATIVE TRAIT LOCI (MQTLS) ARE THE GENETIC VARIANTS THAT MAY AFFECT THE DNA METHYLATION PATTERNS OF CPG SITES. HOWEVER, THEIR ROLES IN INFLUENCING THE DISTURBANCES OF SMOKING-RELATED EPIGENETIC CHANGES HAVE NOT BEEN WELL ESTABLISHED. THIS STUDY WAS CONDUCTED TO ADDRESS WHETHER MQTLS EXIST IN THE VICINITY OF SMOKING-RELATED CPG SITES (+/- 50 KB) AND TO EXAMINE THEIR ASSOCIATIONS WITH SMOKING EXPOSURE AND ALL-CAUSE MORTALITY IN OLDER ADULTS. RESULTS: WE OBTAINED DNA METHYLATION PROFILES IN WHOLE BLOOD SAMPLES BY ILLUMINA INFINIUM HUMAN METHYLATION 450 BEADCHIP ARRAY OF TWO INDEPENDENT SUBSAMPLES OF THE ESTHER STUDY (DISCOVERY SET, N = 581; VALIDATION SET, N = 368) AND THEIR CORRESPONDING GENOTYPING DATA USING THE ILLUMINA INFINIUM ONCOARRAY BEADCHIP. AFTER CORRECTION FOR MULTIPLE TESTING (FDR), WE SUCCESSFULLY IDENTIFIED THAT 70 OUT OF 151 PREVIOUSLY REPORTED SMOKING-RELATED CPG SITES WERE SIGNIFICANTLY ASSOCIATED WITH 192 SNPS WITHIN THE 50 KB SEARCH WINDOW OF EACH LOCUS. THE 192 MQTLS SIGNIFICANTLY INFLUENCED THE ACTIVE SMOKING-RELATED DNA METHYLATION CHANGES, WITH PERCENTAGE CHANGES RANGING FROM 0.01 TO 18.96%, ESPECIALLY FOR THE WEAKLY/MODERATELY SMOKING-RELATED CPG SITES. HOWEVER, THESE IDENTIFIED MQTLS WERE NOT DIRECTLY ASSOCIATED WITH ACTIVE SMOKING EXPOSURE OR ALL-CAUSE MORTALITY. CONCLUSIONS: OUR FINDINGS CLEARLY DEMONSTRATED THAT IF NOT DEALT WITH PROPERLY, THE MQTLS MIGHT IMPAIR THE POWER OF EPIGENETIC-BASED MODELS OF SMOKING EXPOSURE TO A CERTAIN EXTENT. IN ADDITION, SUCH GENETIC VARIANTS COULD BE THE KEY FACTOR TO DISTINGUISH BETWEEN THE HERITABLE AND SMOKING-INDUCED IMPACT ON EPIGENOME DISPARITIES. THESE MQTLS ARE OF SPECIAL IMPORTANCE WHEN DNA METHYLATION MARKERS MEASURED BY ILLUMINA INFINIUM ASSAY ARE USED FOR ANY COMPARATIVE POPULATION STUDIES RELATED TO SMOKING-RELATED CANCERS AND CHRONIC DISEASES. 2017 7 5092 43 PLACENTAL EPIGENETIC MARKS RELATED TO GESTATIONAL WEIGHT GAIN REVEAL POTENTIAL GENES ASSOCIATED WITH OFFSPRING OBESITY PARAMETERS. OBJECTIVE: OFFSPRING EXPOSED TO GESTATIONAL OBESITY HAVE AN INCREASED RISK FOR CHRONIC DISEASES. INCREASING EVIDENCE SUGGESTS THAT EPIGENETICS MAY PLAY A MECHANISTIC ROLE IN METABOLIC PROGRAMMING. THIS STUDY AIMED TO IDENTIFY PLACENTAL DNA METHYLATION MARKS ASSOCIATED WITH GESTATIONAL WEIGHT GAIN (GWG) AND TO STUDY THEIR ASSOCIATION WITH OFFSPRING OBESITY PARAMETERS AT SCHOOL AGE. METHODS: A GLOBAL METHYLATION ARRAY WAS PERFORMED IN 24 PLACENTAS FROM MOTHERS WITH DIFFERENT DEGREES OF GWG (SCREENING SAMPLE). THE METHYLATION PERCENTAGE OF FOUR CYTOSINE-GUANINE (CPG) SITES AND THE RELATIVE EXPRESSION OF THE RESPECTIVE ANNOTATED GENES WERE STUDIED IN 90 ADDITIONAL PLACENTAS (VALIDATION SAMPLE). ASSOCIATIONS OF THESE EPIGENETIC MARKS WITH CLINICAL PARAMETERS IN THE OFFSPRING AT 6 YEARS OF AGE WERE EXAMINED. RESULTS: THE SCREENING ANALYSIS IDENTIFIED 104 CPG SITES (97 GENES) ASSOCIATED WITH GWG. THE VALIDATION ANALYSIS OF FOUR SELECTED CPG SITES (ANNOTATING FOR FRAT1, SNX5, AND KCNK3 GENES) SHOWED THAT THE UPREGULATION OF SNX5 METHYLATION, THE DOWNREGULATION OF FRAT1 METHYLATION, AND KCNK3 UNDEREXPRESSION ASSOCIATED WITH AN ADVERSE METABOLIC PHENOTYPE IN CHILDREN OF WOMEN WITH INCREASED GWG. CONCLUSIONS: THESE RESULTS SUGGEST THAT PLACENTAL REGULATION OF FRAT1, SNX5, AND KCNK3 RELATES TO OBESITY PARAMETERS IN OFFSPRING EXPOSED TO EXCESSIVE GWG AND THEREBY COULD CONDITION THE RISK FOR FUTURE METABOLIC DISORDERS. 2023 8 3125 30 GHSR DNA HYPERMETHYLATION IS A COMMON EPIGENETIC ALTERATION OF HIGH DIAGNOSTIC VALUE IN A BROAD SPECTRUM OF CANCERS. IDENTIFICATION OF A SINGLE MOLECULAR TRAIT THAT IS DETERMINANT OF COMMON MALIGNANCIES MAY SERVE AS A POWERFUL DIAGNOSTIC SUPPLEMENT TO CANCER TYPE-SPECIFIC MARKERS. HERE, WE REPORT A DNA METHYLATION MARK THAT IS CHARACTERISTIC OF SEVEN STUDIED MALIGNANCIES, NAMELY CANCERS OF LUNG, BREAST, PROSTATE, PANCREAS, COLORECTUM, GLIOBLASTOMA AND B CELL CHRONIC LYMPHOCYTIC LEUKAEMIA (CLL) (N = 137). THIS MARK WAS DEFINED BY SUBSTANTIAL HYPERMETHYLATION AT THE PROMOTER AND FIRST EXON OF GROWTH HORMONE SECRETAGOUGE RECEPTOR (GHSR) THROUGH BISULFITE PYROSEQUENCING. THE DEGREE OF ABERRANT METHYLATION WAS CAPABLE OF ACCURATE DISCRIMINATION BETWEEN CANCER AND CONTROL SAMPLES. THE HIGHEST SENSITIVITY AND SPECIFICITY OF CANCER DETECTION WAS ACHIEVED FOR CANCERS OF PANCREAS, LUNG, BREAST AND CLL YIELDING THE AREA UNDER THE CURVE (AUC) VALUES OF 1.0000, 0.9952, 0.9800 AND 0.9400, RESPECTIVELY. NARROWING TO A SINGLE CPG SITE WITHIN THE GENE'S PROMOTER OR FOUR CONSECUTIVE CPG UNITS OF THE HIGHEST METHYLATION LEVELS WITHIN THE FIRST EXON IMPROVED THE DETECTION POWER. GHSR HYPERMETHYLATION WAS DETECTED ALREADY AT THE EARLY STAGE TUMORS. THE ACCURATE PERFORMANCE OF THIS MARKER WAS FURTHER REPLICATED IN AN INDEPENDENT SET OF PANCREATIC CANCER AND CONTROL SAMPLES (N = 78). THESE FINDINGS SUPPORT THE CANDIDATURE OF GHSR METHYLATION AS A HIGHLY ACCURATE PAN-CANCER MARKER. 2015 9 2967 44 GENETIC AND EPIGENETIC REGULATION OF CATECHOL-O-METHYLTRANSFERASE IN RELATION TO INFLAMMATION IN CHRONIC FATIGUE SYNDROME AND FIBROMYALGIA. BACKGROUND: CATECHOL-O-METHYLTRANSFERASE (COMT) HAS BEEN SHOWN TO INFLUENCE CLINICAL PAIN, DESCENDING MODULATION, AND EXERCISE-INDUCED SYMPTOM WORSENING. COMT REGULATES NOCICEPTIVE PROCESSING AND INFLAMMATION, KEY PATHOPHYSIOLOGICAL FEATURES OF CHRONIC FATIGUE SYNDROME AND FIBROMYALGIA (CFS/FM). WE AIMED TO DETERMINE THE INTERACTIONS BETWEEN GENETIC AND EPIGENETIC MECHANISMS REGULATING COMT AND ITS INFLUENCE ON INFLAMMATORY MARKERS AND SYMPTOMS IN PATIENTS WITH CFS/FM. METHODS: A CASE-CONTROL STUDY WITH REPEATED-MEASURES DESIGN WAS USED TO REDUCE THE CHANCE OF FALSE POSITIVE AND INCREASE THE POWER OF OUR FINDINGS. FIFTY-FOUR PARTICIPANTS (28 PATIENTS WITH CFS/FM AND 26 CONTROLS) WERE ASSESSED TWICE WITHIN 4 DAYS. THE ASSESSMENT INCLUDED CLINICAL QUESTIONNAIRES, NEUROPHYSIOLOGICAL ASSESSMENT (PAIN THRESHOLDS, TEMPORAL SUMMATION, AND CONDITIONED PAIN MODULATION), AND BLOOD WITHDRAWAL IN ORDER TO ASSESS RS4818, RS4633, AND RS4680 COMT POLYMORPHISMS AND PERFORM HAPLOTYPE ESTIMATION, DNA METHYLATION IN THE COMT GENE (BOTH MB-COMT AND S-COMT PROMOTERS), AND CYTOKINE EXPRESSION (TNF-ALPHA, IFN-GAMMA, IL-6, AND TGF-BETA). RESULTS: COMT HAPLOTYPES WERE ASSOCIATED WITH DNA METHYLATION IN THE S-COMT PROMOTER, TGF-BETA EXPRESSION, AND SYMPTOMS. HOWEVER, THIS WAS NOT SPECIFIC FOR ONE CONDITION. SIGNIFICANT BETWEEN-GROUP DIFFERENCES WERE FOUND FOR INCREASED DNA METHYLATION IN THE MB-COMT PROMOTER AND DECREASED IFN-GAMMA EXPRESSION IN PATIENTS. DISCUSSION: OUR RESULTS ARE CONSISTENT WITH BASIC AND CLINICAL RESEARCH, PROVIDING INTERESTING INSIGHTS INTO GENETIC-EPIGENETIC REGULATORY MECHANISMS. MB-COMT DNA METHYLATION MIGHT BE AN INDEPENDENT FACTOR CONTRIBUTING TO THE PATHOPHYSIOLOGY OF CFS/FM. FURTHER RESEARCH ON DNA METHYLATION IN COMPLEX CONDITIONS SUCH AS CFS/FM IS WARRANTED. WE RECOMMEND FUTURE RESEARCH TO EMPLOY A REPEATED-MEASURE DESIGN TO CONTROL FOR BIOMARKERS VARIABILITY AND WITHIN-SUBJECT CHANGES. 2022 10 546 49 ATTENUATED EXPRESSION OF SLCO2A1 CAUSED BY DNA METHYLATION IN PEDIATRIC INFLAMMATORY BOWEL DISEASE. BACKGROUND: SLCO2A1 ENCODES A PROSTAGLANDIN (PG) TRANSPORTER, AND AUTOSOMAL RECESSIVE PATHOGENIC VARIANTS OF THIS GENE CAUSE CHRONIC ENTEROPATHY ASSOCIATED WITH SLCO2A1. IT IS UNCLEAR WHETHER A HETEROZYGOUS PATHOGENIC VARIANT OF SLCO2A1 HAS A ROLE IN THE PATHOGENESIS OF OTHER TYPES OF INFLAMMATORY BOWEL DISEASE (IBD). IN THIS STUDY, WE INVESTIGATED THE POSSIBLE INVOLVEMENT OF A LOCAL EPIGENETIC ALTERATION IN SLCO2A1 IN PATIENTS WITH A HETEROZYGOUS PATHOGENIC VARIANT. METHODS: WE CONDUCTED WHOLE-EXOME SEQUENCING OF SAMPLES FROM 2 SISTERS WITH SUSPECTED MONOGENIC IBD. IN ADDITION, WE PERFORMED BISULFITE SEQUENCING USING DNA EXTRACTED FROM THEIR SMALL AND LARGE INTESTINE SAMPLES TO EXPLORE EPIGENETIC ALTERATIONS. RESULTS: A HETEROZYGOUS SPLICING SITE VARIANT, SLCO2A1:C.940 + 1G > A, WAS DETECTED IN BOTH PATIENTS. TO EXPLORE THE POSSIBLE INVOLVEMENT OF EPIGENETIC ALTERATIONS, WE ANALYZED PROTEIN AND MESSENGER RNA EXPRESSION OF SLCO2A1, AND OBSERVED ATTENUATED SLCO2A1 EXPRESSION IN THE INFLAMED LESIONS OF THESE PATIENTS COMPARED WITH THAT IN THE CONTROL INDIVIDUALS. FURTHERMORE, BISULFITE SEQUENCING INDICATED DENSE METHYLATION IN THE PROMOTER REGION OF SLCO2A1 ONLY IN THE INFLAMED LESIONS OF BOTH PATIENTS. THE URINARY PG METABOLITE LEVELS IN THESE PATIENTS WERE COMPARABLE TO THOSE IN PATIENTS WITH CHRONIC ENTEROPATHY ASSOCIATED WITH SLCO2A1 AND HIGHER THAN THOSE IN THE CONTROL INDIVIDUALS. WE FOUND CONSIDERABLY HIGHER LEVELS OF THE METABOLITES IN PATIENT 1, WHO SHOWED MORE SEVERE SYMPTOMS THAN PATIENT 2. CONCLUSIONS: LOCAL DNA METHYLATION ATTENUATED SLCO2A1 EXPRESSION, WHICH MAY EVOKE LOCAL INFLAMMATION OF THE MUCOSA BY THE UNINCORPORATED PG. THESE FINDINGS MAY IMPROVE OUR UNDERSTANDING OF THE EPIGENETIC MECHANISMS UNDERLYING IBD DEVELOPMENT. 2023 11 5887 45 SYSTEMIC STEROID EXPOSURE IS ASSOCIATED WITH DIFFERENTIAL METHYLATION IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE. RATIONALE: SYSTEMIC GLUCOCORTICOIDS ARE USED THERAPEUTICALLY TO TREAT A VARIETY OF MEDICAL CONDITIONS. EPIGENETIC PROCESSES SUCH AS DNA METHYLATION MAY REFLECT EXPOSURE TO GLUCOCORTICOIDS AND MAY BE INVOLVED IN MEDIATING THE RESPONSES AND SIDE EFFECTS ASSOCIATED WITH THESE MEDICATIONS. OBJECTIVES: TO TEST THE HYPOTHESIS THAT DIFFERENCES IN DNA METHYLATION ARE ASSOCIATED WITH CURRENT SYSTEMIC STEROID USE. METHODS: WE OBTAINED DNA METHYLATION DATA AT 27,578 CPG SITES IN 14,475 GENES THROUGHOUT THE GENOME IN TWO LARGE, INDEPENDENT COHORTS: THE INTERNATIONAL COPD GENETICS NETWORK (N(DISCOVERY) = 1,085) AND THE BOSTON EARLY ONSET COPD STUDY (N(REPLICATION) = 369). SITES WERE TESTED FOR ASSOCIATION WITH CURRENT SYSTEMIC STEROID USE USING GENERALIZED LINEAR MIXED MODELS. MEASUREMENTS AND MAIN RESULTS: A TOTAL OF 511 SITES DEMONSTRATED SIGNIFICANT DIFFERENTIAL METHYLATION BY SYSTEMIC CORTICOSTEROID USE IN ALL THREE OF OUR PRIMARY MODELS. PYROSEQUENCING VALIDATION CONFIRMED ROBUST DIFFERENTIAL METHYLATION AT CPG SITES ANNOTATED TO GENES SUCH AS SLC22A18, LRP3, HIPK3, SCNN1A, FXYD1, IRF7, AZU1, SIT1, GPR97, ABHD16B, AND RABGEF1. FUNCTIONAL ANNOTATION CLUSTERING DEMONSTRATED SIGNIFICANT ENRICHMENT IN INTRINSIC MEMBRANE COMPONENTS, HEMOSTASIS AND COAGULATION, CELLULAR ION HOMEOSTASIS, LEUKOCYTE AND LYMPHOCYTE ACTIVATION AND CHEMOTAXIS, PROTEIN TRANSPORT, AND RESPONSES TO NUTRIENTS. CONCLUSIONS: OUR ANALYSES SUGGEST THAT SYSTEMIC STEROID USE IS ASSOCIATED WITH SITE-SPECIFIC DIFFERENTIAL METHYLATION THROUGHOUT THE GENOME. DIFFERENTIALLY METHYLATED CPG SITES WERE FOUND IN BIOLOGICALLY PLAUSIBLE AND PREVIOUSLY UNSUSPECTED PATHWAYS; THESE GENES AND PATHWAYS MAY BE RELEVANT IN THE DEVELOPMENT OF NOVEL TARGETED THERAPIES. 2012 12 11 43 15Q12 VARIANTS, SPUTUM GENE PROMOTER HYPERMETHYLATION, AND LUNG CANCER RISK: A GWAS IN SMOKERS. BACKGROUND: LUNG CANCER IS THE LEADING CAUSE OF CANCER-RELATED MORTALITY WORLDWIDE. DETECTION OF PROMOTER HYPERMETHYLATION OF TUMOR SUPPRESSOR GENES IN EXFOLIATED CELLS FROM THE LUNG PROVIDES AN ASSESSMENT OF FIELD CANCERIZATION THAT IN TURN PREDICTS LUNG CANCER. THE IDENTIFICATION OF GENETIC DETERMINANTS FOR THIS VALIDATED CANCER BIOMARKER SHOULD PROVIDE NOVEL INSIGHTS INTO MECHANISMS UNDERLYING EPIGENETIC REPROGRAMMING DURING LUNG CARCINOGENESIS. METHODS: A GENOME-WIDE ASSOCIATION STUDY USING GENERALIZED ESTIMATING EQUATIONS AND LOGISTIC REGRESSION MODELS WAS CONDUCTED IN TWO GEOGRAPHICALLY INDEPENDENT SMOKER COHORTS TO IDENTIFY LOCI AFFECTING THE PROPENSITY FOR CANCER-RELATED GENE METHYLATION THAT WAS ASSESSED BY A 12-GENE PANEL INTERROGATED IN SPUTUM. ALL STATISTICAL TESTS WERE TWO-SIDED. RESULTS: TWO SINGLE NUCLEOTIDE POLYMORPHISMS (SNPS) AT 15Q12 (RS73371737 AND RS7179575) THAT DROVE GENE METHYLATION WERE DISCOVERED AND REPLICATED WITH RS73371737 REACHING GENOME-WIDE SIGNIFICANCE (P = 3.3X10(-8)). A HAPLOTYPE CARRYING RISK ALLELES FROM THE TWO 15Q12 SNPS CONFERRED 57% INCREASED RISK FOR GENE METHYLATION (P = 2.5X10(-9)). RS73371737 REDUCED GABRB3 EXPRESSION IN LUNG CELLS AND INCREASED RISK FOR SMOKING-INDUCED CHRONIC MUCOUS HYPERSECRETION. FURTHERMORE, SUBJECTS WITH VARIANT HOMOZYGOTE OF RS73371737 HAD A TWO-FOLD INCREASE IN RISK FOR LUNG CANCER (P = .0043). PATHWAY ANALYSIS IDENTIFIED DNA DOUBLE-STRAND BREAK REPAIR BY HOMOLOGOUS RECOMBINATION (DSBR-HR) AS A MAJOR PATHWAY AFFECTING SUSCEPTIBILITY FOR GENE METHYLATION THAT WAS VALIDATED BY MEASURING CHROMATID BREAKS IN LYMPHOCYTES CHALLENGED BY BLEOMYCIN. CONCLUSIONS: A FUNCTIONAL 15Q12 VARIANT WAS IDENTIFIED AS A RISK FACTOR FOR GENE METHYLATION AND LUNG CANCER. THE ASSOCIATIONS COULD BE MEDIATED BY GABAERGIC SIGNALING THAT DRIVES THE SMOKING-INDUCED MUCOUS CELL METAPLASIA. OUR FINDINGS ALSO SUBSTANTIATE DSBR-HR AS A CRITICAL PATHWAY DRIVING EPIGENETIC GENE SILENCING. 2015 13 4736 50 NOVEL EPIGENETIC BIOMARKERS MEDIATING BISPHENOL A EXPOSURE AND METABOLIC PHENOTYPES IN FEMALE MICE. THERE IS COMPELLING EVIDENCE THAT EPIGENETIC MODIFICATIONS LINK DEVELOPMENTAL ENVIRONMENTAL INSULTS TO ADULT DISEASE SUSCEPTIBILITY. ANIMAL STUDIES HAVE ASSOCIATED PERINATAL BISPHENOL A (BPA) EXPOSURE TO ALTERED DNA METHYLATION, BUT THESE STUDIES ARE OFTEN LIMITED TO CANDIDATE GENE AND GLOBAL NON-LOCI-SPECIFIC APPROACHES. BY USING AN EPIGENOME-WIDE DISCOVERY PLATFORM, WE ELUCIDATED EPIGENETIC ALTERATIONS IN LIVER TISSUE FROM ADULT MICE OFFSPRING (10 MONTHS) FOLLOWING PERINATAL BPA EXPOSURE AT HUMAN PHYSIOLOGICALLY RELEVANT DOSES (50-NG, 50-MUG, AND 50-MG BPA/KG DIET). BIOLOGICAL PATHWAY ANALYSIS IDENTIFIED AN ENRICHMENT OF SIGNIFICANT DIFFERENTIALLY METHYLATED REGIONS IN METABOLIC PATHWAYS AMONG FEMALES. FURTHERMORE, THROUGH THE USE OF TOP ENRICHED BIOLOGICAL PATHWAYS, 4 CANDIDATE GENES WERE CHOSEN TO ASSESS DNA METHYLATION AS A MEDIATING FACTOR LINKING THE ASSOCIATION OF PERINATAL BPA EXPOSURE TO METABOLIC PHENOTYPES PREVIOUSLY OBSERVED IN FEMALE OFFSPRING. DNA METHYLATION STATUS AT JANUS KINASE-2 (JAK-2), RETINOID X RECEPTOR (RXR), REGULATORY FACTOR X-ASSOCIATED PROTEIN (RFXAP), AND TRANSMEMBRANE PROTEIN 238 (TMEM238) WAS USED WITHIN A MEDIATIONAL REGRESSION ANALYSIS. DNA METHYLATION IN ALL FOUR OF THE CANDIDATE GENES WAS IDENTIFIED AS A MEDIATOR IN THE MECHANISTIC PATHWAY OF DEVELOPMENTAL BPA EXPOSURE AND FEMALE-SPECIFIC ENERGY EXPENDITURE, BODY WEIGHT, AND BODY FAT PHENOTYPES. DATA GENERATED FROM THIS STUDY ARE CRUCIAL FOR DECIPHERING THE MECHANISTIC ROLE OF EPIGENETICS IN THE PATHOGENESIS OF CHRONIC DISEASE AND THE DEVELOPMENT OF EPIGENETIC-BASED PREVENTION AND THERAPEUTIC STRATEGIES FOR COMPLEX HUMAN DISEASE. 2017 14 1138 38 COMPUTATIONAL METHODS FOR DETECTION OF DIFFERENTIALLY METHYLATED REGIONS USING KERNEL DISTANCE AND SCAN STATISTICS. MOTIVATION: 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 SEQUENCE OF DNA. ABNORMAL DNA METHYLATION IS ASSOCIATED WITH MANY HUMAN DISEASES. RESULTS: WE PROPOSE TWO DIFFERENT APPROACHES TO TEST FOR DIFFERENTIALLY METHYLATED REGIONS (DMRS) ASSOCIATED WITH COMPLEX TRAITS, WHILE ACCOUNTING FOR CORRELATIONS AMONG CPG SITES IN THE DMRS. THE FIRST APPROACH IS A NONPARAMETRIC METHOD USING A KERNEL DISTANCE STATISTIC AND THE SECOND ONE IS A LIKELIHOOD-BASED METHOD USING A BINOMIAL SPATIAL SCAN STATISTIC. THE KERNEL DISTANCE METHOD USES THE KERNEL FUNCTION, WHILE THE BINOMIAL SCAN STATISTIC APPROACH USES A MIXED-EFFECTS MODEL TO INCORPORATE CORRELATIONS AMONG CPG SITES. EXTENSIVE SIMULATIONS SHOW THAT BOTH APPROACHES HAVE EXCELLENT CONTROL OF TYPE I ERROR, AND BOTH HAVE REASONABLE STATISTICAL POWER. THE BINOMIAL SCAN STATISTIC APPROACH APPEARS TO HAVE HIGHER POWER, WHILE THE KERNEL DISTANCE METHOD IS COMPUTATIONALLY FASTER. THE PROPOSED METHODS ARE DEMONSTRATED USING DATA FROM A CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) STUDY. 2019 15 3050 28 GENOME-WIDE ASSOCIATION ANALYSES FOR LUNG FUNCTION AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE IDENTIFY NEW LOCI AND POTENTIAL DRUGGABLE TARGETS. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS CHARACTERIZED BY REDUCED LUNG FUNCTION AND IS THE THIRD LEADING CAUSE OF DEATH GLOBALLY. THROUGH GENOME-WIDE ASSOCIATION DISCOVERY IN 48,943 INDIVIDUALS, SELECTED FROM EXTREMES OF THE LUNG FUNCTION DISTRIBUTION IN UK BIOBANK, AND FOLLOW-UP IN 95,375 INDIVIDUALS, WE INCREASED THE YIELD OF INDEPENDENT SIGNALS FOR LUNG FUNCTION FROM 54 TO 97. A GENETIC RISK SCORE WAS ASSOCIATED WITH COPD SUSCEPTIBILITY (ODDS RATIO PER 1 S.D. OF THE RISK SCORE ( APPROXIMATELY 6 ALLELES) (95% CONFIDENCE INTERVAL) = 1.24 (1.20-1.27), P = 5.05 X 10(-49)), AND WE OBSERVED A 3.7-FOLD DIFFERENCE IN COPD RISK BETWEEN INDIVIDUALS IN THE HIGHEST AND LOWEST GENETIC RISK SCORE DECILES IN UK BIOBANK. THE 97 SIGNALS SHOW ENRICHMENT IN GENES FOR DEVELOPMENT, ELASTIC FIBERS AND EPIGENETIC REGULATION PATHWAYS. WE HIGHLIGHT TARGETS FOR DRUGS AND COMPOUNDS IN DEVELOPMENT FOR COPD AND ASTHMA (GENES IN THE INOSITOL PHOSPHATE METABOLISM PATHWAY AND CHRM3) AND DESCRIBE TARGETS FOR POTENTIAL DRUG REPOSITIONING FROM OTHER CLINICAL INDICATIONS. 2017 16 3296 44 HIGH RESOLUTION INTEGRATIVE ANALYSIS REVEALS WIDESPREAD GENETIC AND EPIGENETIC CHANGES AFTER CHRONIC IN-VITRO ACID AND BILE EXPOSURE IN BARRETT'S EPITHELIUM CELLS. BARRETT'S EPITHELIUM (BE) IS A PREMALIGNANT CONDITION RESULTING FROM CHRONIC GASTROESOPHAGEAL REFLUX THAT MAY PROGRESS TO ESOPHAGEAL ADENOCARCINOMA (EAC). EARLY INTERVENTION HOLDS PROMISE IN PREVENTING BE PROGRESSION. HOWEVER, IDENTIFICATION OF HIGH-RISK BE PATIENTS REMAINS CHALLENGING DUE TO INADEQUATE BIOMARKERS FOR EARLY DIAGNOSIS. WE INVESTIGATED THE EFFECT OF PROLONGED CHRONIC ACID AND BILE EXPOSURE ON TRANSCRIPTOME, METHYLOME, AND MUTATOME OF CELLS IN AN IN-VITRO BE CARCINOGENESIS (BEC) MODEL. TWENTY WEEKS ACID AND BILE EXPOSED CELLS FROM THE BEC MODEL (BEC20W) WERE COMPARED WITH THEIR NAIVE PREDECESSORS HISEQ ILLUMINA BASED RNA SEQUENCING WAS PERFORMED ON RNA FROM BOTH THE CELLS FOR GENE EXPRESSION AND MUTATIONAL ANALYSIS. HELP TAGGING ASSAY WAS PERFORMED FOR DNA METHYLATION ANALYSIS. INGENUITY PATHWAY, GENE ONTOLOGY, AND KEGG PATHWAY ANALYSES WERE THEN PERFORMED ON DATASETS. WIDESPREAD ABERRANT GENETIC AND EPIGENETIC CHANGES WERE OBSERVED IN THE BEC20W CELLS. COMBINATORIAL ANALYSES REVEALED 433 FROM A TOTAL OF 863 DOWNREGULATED GENES HAD ACCOMPANYING HYPERMETHYLATION OF PROMOTERS. SIMULTANEOUSLY, 690 GENES FROM A TOTAL OF 1,492 WERE UPREGULATED WITH ACCOMPANYING PROMOTER HYPOMETHYLATION. IN ADDITION, 763 MUTATIONS WERE IDENTIFIED ON 637 GENES. INGENUITY PATHWAY ANALYSIS, GENE ONTOLOGY, AND KEGG PATHWAY ANALYSES ASSOCIATED THE GENETIC AND EPIGENETIC CHANGES IN BEC20W CELLS WITH CELLULAR AND BIOLOGICAL FUNCTIONS. INTEGRATION OF HIGH RESOLUTION COMPARATIVE ANALYSES OF NAIVE BAR-T AND BEC20W CELLS REVEALED STRIKING GENETIC AND EPIGENETIC CHANGES INDUCED BY CHRONIC ACID AND BILE EXPOSURE THAT MAY DISRUPT NORMAL CELLULAR FUNCTIONS AND PROMOTE CARCINOGENESIS. THIS NOVEL STUDY REVEALS SEVERAL POTENTIAL TARGETS FOR FUTURE BIOMARKERS AND THERAPEUTIC DEVELOPMENT. 2013 17 1846 42 EFFECTS OF TWO TYPES OF ENERGY RESTRICTION ON METHYLATION LEVELS OF ADIPONECTIN RECEPTOR 1 AND LEPTIN RECEPTOR OVERLAPPING TRANSCRIPT IN A MOUSE MAMMARY TUMOUR VIRUS-TRANSFORMING GROWTH FACTOR-ALPHA BREAST CANCER MOUSE MODEL. THE ROLE OF ADIPONECTIN AND LEPTIN SIGNALLING PATHWAYS HAS BEEN SUGGESTED TO PLAY IMPORTANT ROLES IN THE PROTECTIVE EFFECTS OF ENERGY RESTRICTION (ER) ON MAMMARY TUMOUR (MT) DEVELOPMENT. TO STUDY THE EFFECTS OF ER ON THE METHYLATION LEVELS IN ADIPONECTIN RECEPTOR 1 (ADIPOR1) AND LEPTIN RECEPTOR OVERLAPPING TRANSCRIPT (LEPROT) GENES USING THE PYROSEQUENCING METHOD IN MAMMARY FAT PAD TISSUE, MOUSE MAMMARY TUMOUR VIRUS-TRANSFORMING GROWTH FACTOR-ALPHA (MMTV-TGF-ALPHA) FEMALE MICE WERE RANDOMLY ASSIGNED TO AD LIBITUM (AL), CHRONIC ER (CER, 15 % ER) OR INTERMITTENT ER (3 WEEKS AL AND 1 WEEK 60 % ER IN CYCLIC PERIODS) GROUPS AT 10 WEEKS OF AGE UNTIL 82 WEEKS OF AGE. THE METHYLATION LEVELS OF ADIPOR1 IN THE CER GROUP WERE HIGHER THAN THOSE IN THE AL GROUP AT WEEK 49/50 (P < 0.05), WHILE THE LEVELS OF METHYLATION FOR ADIPOR1 AND LEPROT GENES WERE SIMILAR AMONG THE OTHER GROUPS. ALSO, THE METHYLATION LEVELS AT CPG2 AND CPG3 REGIONS OF THE PROMOTER REGION OF THE ADIPOR1 GENE IN THE CER GROUP WERE THREE TIMES HIGHER (P < 0.05), WHILE CPG1 ISLAND OF LEPROT METHYLATION WAS SIGNIFICANTLY LOWER COMPARED WITH THE OTHER GROUPS (P < 0.05). ADIPONECTIN AND LEPTIN GENE EXPRESSION LEVELS WERE CONSISTENT WITH THE METHYLATION LEVELS. WE ALSO OBSERVED A CHANGE WITH AGEING IN METHYLATION LEVELS OF THESE GENES. THESE RESULTS INDICATE THAT DIFFERENT TYPES OF ER MODIFY METHYLATION LEVELS OF ADIPOR1 AND LEPROT IN DIFFERENT WAYS AND CER HAD A MORE SIGNIFICANT EFFECT ON METHYLATION LEVELS OF BOTH GENES. EPIGENETIC REGULATION OF THESE GENES MAY PLAY IMPORTANT ROLES IN THE PREVENTIVE EFFECTS OF ER AGAINST MT DEVELOPMENT AND AGEING PROCESSES. 2021 18 6826 56 [GENOME-WIDE ANALYSIS OF DNA METHYLATION IN CD4+ T LYMPHOCYTES OF PATIENTS WITH PRIMARY PROGRESSIVE MULTIPLE SCLEROSIS INDICATES INVOLVEMENT OF THIS EPIGENETIC PROCESS IN THE DISEASE IMMUNOPATHOGENESIS]. THE PATHOGENESIS OF MULTIPLE SCLEROSIS (MS), A CHRONIC DISEASE OF THE CNS, INCLUDES AUTOIMMUNE AND NEURODEGENERATIVE COMPONENTS. IN MOST CASES, PATIENTS DEVELOP RELAPSING-REMITTING MS (RRMS), WHILE 10-15% OF PATIENTS DEVELOP PRIMARY PROGRESSIVE MS (PPMS), WHICH DIFFERS FROM RRMS IN THE MECHANISMS OF THE PATHOLOGICAL PROCESS, SOME DEMOGRAPHIC, AND SOME CLINICAL CHARACTERISTICS. THESE DIFFERENCES MAY BE EXPLAINED BY THE EPIGENETIC REGULATION OF GENE EXPRESSION IN PPMS INCLUDING DNA METHYLATION AS ONE OF THE KEY EPIGENETIC PROCESSES. THE FEATURES OF DNA METHYLATION IN VARIOUS CELL POPULATIONS IN PPMS PATIENTS REMAIN UNDERSTUDIED. THE GOAL OF THIS STUDY IS TO IDENTIFY DIFFERENTIALLY METHYLATED CPG SITES (DMSS) OF THE GENOME OF CD4+ T LYMPHOCYTES, WHICH CHARACTERIZE PPMS. THE STUDY INCLUDED EIGHT TREATMENT-NAIVE PPMS PATIENTS AND EIGHT HEALTHY CONTROLS. GENOME-WIDE ANALYSIS OF DNA METHYLATION OF CD4+ T LYMPHOCYTES WAS PERFORMED USING HIGH-DENSITY DNA MICROARRAYS. WE HAVE IDENTIFIED 108 DMSS, WHICH DISTINGUISH PPMS PATIENTS FROM HEALTHY CONTROLS. IN PPMS PATIENTS 81% OF THE DMSS ARE HYPERMETHYLATED. MORE THAN A HALF OF THE IDENTIFIED DMSS ARE LOCATED IN KNOWN GENES IN CPG ISLANDS AND ADJACENT REGIONS, WHICH INDICATES A HIGH FUNCTIONAL SIGNIFICANCE OF THESE DMSS IN PPMS DEVELOPMENT. ANALYSIS OF THE OVERREPRESENTATION OF DMS-CONTAINING GENES IN THE MAIN BIOLOGICAL PROCESSES DEMONSTRATES THEIR INVOLVEMENT IN THE REGULATION OF CELL ADHESION TO THE EXTRACELLULAR MATRIX AND THE DEVELOPMENT OF THE IMMUNE RESPONSE, I.E., ANTIGEN PROCESSING AND PRESENTATION, AND DEVELOPMENT OF THE IMMUNE SYSTEM. GENOME-WIDE ANALYSIS OF DNA METHYLATION IN CD4+ T LYMPHOCYTES OF PPMS PATIENTS INDICATES THE INVOLVEMENT OF THIS EPIGENETIC PROCESS IN THE IMMUNOPATHOGENESIS OF THE DISEASE. THESE RESULTS MAY HELP BETTER UNDERSTAND THE PATHOGENESIS OF THIS SEVERE FORM OF MS. 2022 19 4750 38 NOVEL REGIONAL AGE-ASSOCIATED DNA METHYLATION CHANGES WITHIN HUMAN COMMON DISEASE-ASSOCIATED LOCI. BACKGROUND: ADVANCING AGE PROGRESSIVELY IMPACTS ON RISK AND SEVERITY OF CHRONIC DISEASE. IT ALSO MODIFIES THE EPIGENOME, WITH CHANGES IN DNA METHYLATION, DUE TO BOTH RANDOM DRIFT AND VARIATION WITHIN SPECIFIC FUNCTIONAL LOCI. RESULTS: IN A DISCOVERY SET OF 2238 PERIPHERAL-BLOOD GENOME-WIDE DNA METHYLOMES AGED 19-82 YEARS, WE IDENTIFY 71 AGE-ASSOCIATED DIFFERENTIALLY METHYLATED REGIONS WITHIN THE LINKAGE DISEQUILIBRIUM BLOCKS OF THE SINGLE NUCLEOTIDE POLYMORPHISMS FROM THE NIH GENOME-WIDE ASSOCIATION STUDY CATALOGUE. THIS INCLUDED 52 NOVEL REGIONS, 29 WITHIN LOCI NOT COVERED BY 450 K OR 27 K ILLUMINA ARRAY, AND WITH ENRICHMENT FOR DNASE-I HYPERSENSITIVITY SITES ACROSS THE FULL RANGE OF TISSUES. THESE AGE-ASSOCIATED DIFFERENTIALLY METHYLATED REGIONS ALSO SHOW MARKED ENRICHMENT FOR ENHANCERS AND POISED PROMOTERS ACROSS MULTIPLE CELL TYPES. IN A REPLICATION SET OF 2084 DNA METHYLOMES, 95.7 % OF THE AGE-ASSOCIATED DIFFERENTIALLY METHYLATED REGIONS SHOWED THE SAME DIRECTION OF AGEING EFFECT, WITH 80.3 % AND 53.5 % REPLICATED TO P < 0.05 AND P < 1.85 X 10(-8), RESPECTIVELY. CONCLUSION: BY ANALYSING THE FUNCTIONALLY ENRICHED DISEASE AND TRAIT-ASSOCIATED REGIONS OF THE HUMAN GENOME, WE IDENTIFY NOVEL EPIGENETIC AGEING CHANGES, WHICH COULD BE USEFUL BIOMARKERS OR PROVIDE MECHANISTIC INSIGHTS INTO AGE-RELATED COMMON DISEASES. 2016 20 1607 46 DNA METHYLATION, COLON CANCER AND MEDITERRANEAN DIET: RESULTS FROM THE EPIC-ITALY COHORT. THE BIOLOGICAL MECHANISMS THROUGH WHICH ADHERENCE TO MEDITERRANEAN DIET (MD) PROTECTS AGAINST COLON CANCER (CC) ARE POORLY UNDERSTOOD. EVIDENCE SUGGESTS THAT CHRONIC INFLAMMATION MAY BE IMPLICATED IN THE PATHWAY. BOTH DIET AND CC ARE RELATED TO EPIGENETIC REGULATION. WE PERFORMED A NESTED CASE-CONTROL STUDY ON 161 PAIRS FROM THE ITALIAN COMPONENT OF THE EUROPEAN PROSPECTIVE INVESTIGATION INTO CANCER AND NUTRITION (EPIC) COHORT, IN WHICH WE LOOKED FOR THE METHYLATION SIGNALS IN DNA EXTRACTED FROM LEUCOCYTES ASSOCIATED WITH BOTH CC AND MD IN 995 CPGS LOCATED IN 48 INFLAMMATION GENES. THE DNA METHYLATION SIGNALS DETECTED IN THIS ANALYSIS WERE VALIDATED IN A SUBGROUP OF 47 CASE-CONTROL PAIRS AND FURTHER REPLICATED (WHERE VALIDATED) IN 95 NEW PAIRS BY MEANS OF PYROSEQUENCING. AMONG THE CPG SITES SELECTED A-PRIORI IN INFLAMMATION-RELATED GENES, SEVEN CPG SITES WERE FOUND TO BE ASSOCIATED WITH CC STATUS AND WITH MD, IN LINE WITH ITS PROTECTIVE EFFECT. ONLY TWO CPG SITES (CG17968347-SERPINE1 AND CG20674490-RUNX3) WERE VALIDATED USING BISULPHITE PYROSEQUENCING AND, AFTER REPLICATION, WE FOUND THAT DNA METHYLATION OF CG20674490-RUNX3 MAY BE A POTENTIAL MOLECULAR MEDIATOR EXPLAINING THE PROTECTIVE EFFECT OF MD ON CC ONSET. THE USE OF A 'MEET-IN-THE-MIDDLE' APPROACH TO IDENTIFY THE OVERLAP BETWEEN EXPOSURE AND PREDICTIVE MARKERS OF DISEASE IS INNOVATIVE IN STUDIES ON THE RELATIONSHIP BETWEEN DIET AND CANCER, IN WHICH EXPOSURE ASSESSMENT IS DIFFICULT AND THE MECHANISMS THROUGH WHICH THE NUTRIENTS EXERT THEIR PROTECTIVE EFFECT IS LARGELY UNKNOWN. 2019