1 1541 115 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 2 5092 36 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 3 1782 39 EFFECT OF A 3-WEEK MULTIDISCIPLINARY BODY WEIGHT REDUCTION PROGRAM ON THE EPIGENETIC AGE ACCELERATION IN OBESE ADULTS. OBESITY AND AGING SHARE COMMON MOLECULAR AND CELLULAR MECHANISMS UNDERLYING THE PATHOPHYSIOLOGY OF CARDIOVASCULAR DISEASES (CVD), WHICH OCCUR FREQUENTLY IN BOTH CONDITIONS. DNA METHYLATION (DNAM) AGE, A BIOMARKER OF THE EPIGENETIC CLOCK, HAS BEEN PROPOSED AS A MORE ACCURATE PREDICTOR OF BIOLOGICAL AGING THAN CHRONOLOGICAL AGE. A POSITIVE DIFFERENCE BETWEEN AN INDIVIDUAL'S CHRONOLOGICAL AGE AND DNAM AGE IS REFERRED TO AS EPIGENETIC AGE ACCELERATION. THE OBJECTIVE OF THE PRESENT STUDY WAS TO EVALUATE THE EFFECTS OF A 3-WEEK IN-HOSPITAL BODY WEIGHT REDUCTION PROGRAM (BWRP) ON THE EPIGENETIC AGE ACCELERATION, AS WELL AS ON OTHER CARDIOMETABOLIC OUTCOMES, IN A COHORT OF 72 OBESE ADULTS (F/M: 43/29; (CHRONOLOGICAL) AGE: 51.5 +/- 14.5 YRS; BMI: 46.5 +/- 6.3 KG/M2). AT THE END OF THE BWRP, WHEN CONSIDERING THE ENTIRE POPULATION, BMI DECREASED, AND CHANGES IN BODY COMPOSITION WERE OBSERVED. THE BWRP ALSO PRODUCED BENEFICIAL METABOLIC EFFECTS AS DEMONSTRATED BY DECREASES IN GLUCOSE, INSULIN, HOMA-IR, TOTAL CHOLESTEROL, AND LDL CHOLESTEROL. A POST-BWRP IMPROVEMENT IN CARDIOVASCULAR FUNCTION WAS ALSO EVIDENT (I.E., DECREASES IN SYSTOLIC AND DIASTOLIC BLOOD PRESSURES AND HEART RATE). THE BWRP REDUCED SOME MARKERS OF SYSTEMIC INFLAMMATION, PARTICULARLY C-REACTIVE PROTEIN (CRP). FINALLY, VASCULAR AGE (VA) AND FRAMINGHAM RISK SCORE (FRS) WERE REDUCED AFTER THE BWRP. WHEN CONSIDERING THE ENTIRE POPULATION, DNAM AGE AND EPIGENETIC AGE ACCELERATION DID NOT DIFFER AFTER THE BWRP. HOWEVER, WHEN SUBDIVIDING THE POPULATION INTO TWO GROUPS BASED ON EACH SUBJECT'S EPIGENETIC AGE ACCELERATION (I.E., 0 YRS), THE BWRP REDUCED THE EPIGENETIC AGE ACCELERATION ONLY IN OBESE SUBJECTS WITH A VALUE > 0 YRS (THUS BIOLOGICALLY OLDER THAN EXPECTED). AMONG ALL THE SINGLE DEMOGRAPHIC, LIFESTYLE, BIOCHEMICAL, AND CLINICAL CHARACTERISTICS INVESTIGATED, ONLY SOME MARKERS OF SYSTEMIC INFLAMMATION, SUCH AS CRP, WERE ASSOCIATED WITH THE EPIGENETIC AGE ACCELERATION. MOREOVER, CHRONOLOGICAL AGE WAS CORRELATED WITH DNAM AGE AND VA; FINALLY, THERE WAS A CORRELATION BETWEEN DNAM AGE AND VA. IN CONCLUSION, A 3-WEEK BWRP IS CAPABLE OF REDUCING THE EPIGENETIC AGE ACCELERATION IN OBESE ADULTS, BEING THE BWRP-INDUCED REJUVENATION EVIDENT IN SUBJECTS WITH AN EPIGENETIC AGE ACCELERATION > 0 YRS. BASED ON THE BWRP-INDUCED DECREASE IN CRP LEVELS, CHRONIC SYSTEMIC INFLAMMATION SEEMS TO PLAY A ROLE IN MEDIATING OBESITY-RELATED EPIGENETIC REMODELING AND BIOLOGICAL AGING. THUS, DUE TO THE STRONG ASSOCIATION OF CVD RISK WITH THE EPIGENETIC CLOCK AND MORBIDITY/MORTALITY, ANY EFFORT SHOULD BE MADE TO REDUCE THE LOW-GRADE CHRONIC INFLAMMATORY STATE IN OBESITY. 2022 4 3073 38 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 5 4736 33 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 6 1529 29 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 7 275 31 AGE-RELATED CLONAL HAEMOPOIESIS IS ASSOCIATED WITH INCREASED EPIGENETIC AGE. AGE-RELATED CLONAL HAEMOPOIESIS (ARCH) IN HEALTHY INDIVIDUALS WAS INITIALLY OBSERVED THROUGH AN INCREASED SKEWING IN X-CHROMOSOME INACTIVATION [1]. MORE RECENTLY, SEVERAL GROUPS REPORTED THAT ARCH IS DRIVEN BY SOMATIC MUTATIONS [2], WITH THE MOST PREVALENT ARCH MUTATIONS BEING IN THE DNMT3A AND TET2 GENES, PREVIOUSLY DESCRIBED AS DRIVERS OF MYELOID MALIGNANCIES. ARCH IS ASSOCIATED WITH AN INCREASED RISK FOR HAEMATOLOGICAL CANCERS [2]. ARCH ALSO CONFERS AN INCREASED RISK FOR NON-HAEMATOLOGICAL DISEASES, SUCH AS CARDIOVASCULAR DISEASE, ATHEROSCLEROSIS, AND CHRONIC ISCHEMIC HEART FAILURE, FOR WHICH AGE IS A MAIN RISK FACTOR [3,4]. WHETHER ARCH IS LINKED TO ACCELERATED AGEING HAS REMAINED UNEXPLORED. THE MOST ACCURATE AND COMMONLY USED TOOLS TO MEASURE AGE ACCELERATION ARE EPIGENETIC CLOCKS: THEY ARE BASED ON AGE-RELATED METHYLATION DIFFERENCES AT SPECIFIC CPG SITES [5]. DEVIATIONS FROM CHRONOLOGICAL AGE TOWARDS AN INCREASED EPIGENETIC AGE HAVE BEEN ASSOCIATED WITH INCREASED RISK OF EARLIER MORTALITY AND AGE-RELATED MORBIDITIES [5,6]. HERE WE PRESENT EVIDENCE OF ACCELERATED EPIGENETIC AGE IN INDIVIDUALS WITH ARCH. 2019 8 2967 28 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 9 546 25 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 10 181 23 ACCELERATED EPIGENETIC AGING MEDIATES THE ASSOCIATION BETWEEN VITAMIN D LEVELS AND KNEE PAIN IN COMMUNITY-DWELLING INDIVIDUALS. OBJECTIVES: TO EXAMINE THE RELATIONSHIP BETWEEN VITAMIN D STATUS AND PAIN INTENSITY AND DISABILITY IN INDIVIDUALS WITH AND WITHOUT KNEE PAIN, AND TO EXAMINE THE ROLE OF EPIGENETICS IN THIS RELATIONSHIP. DESIGN: CROSS-SECTIONAL ANALYSIS OF DATA FROM THE UPLOAD-2 STUDY (UNDERSTANDING PAIN AND LIMITATIONS IN OSTEOARTHRITIC DISEASE-2). PARTICIPANTS: 189 INDIVIDUALS AGED 45-65 YEARS AND OLDER. MEASUREMENTS: SERUM VITAMIN D LEVELS, PAIN RELATED INTERFERENCE AND CHARACTERISTIC PAIN INTENSITY MEASURES, AND THE EPIGENETIC CLOCK GRIMAGE DERIVED FROM BLOOD ANALYSES. RESULTS: LOWER VITAMIN D WAS ASSOCIATED WITH ADVANCED EPIGENETIC AGING (AGEACCELGRIM), GREATER PAIN AND DISABILITY AND THAT (AGEACCELGRIM) MEDIATED THE RELATIONSHIP BETWEEN VITAMIN D STATUS AND SELF-REPORTED PAIN (AB = -0.0799; CI [-0.1492, -0.0237]) AND DISABILITY (AB = -0.0669; CI [-0.1365, -0.0149]) OUTCOMES. CONCLUSION: THESE DATA SUPPORT THE NOTION THAT LIFESTYLE FACTORS SUCH AS NUTRITION STATUS PLAY A KEY ROLE IN AGING PROCESS, AS WELL AS THE DEVELOPMENT AND MAINTENANCE OF AGE-RELATED DISEASES SUCH AS PAIN. MODIFYING NUTRITION STATUS COULD HELP PROMOTE HEALTHY AGING AND REDUCE PAIN. 2022 11 1990 28 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 12 5095 26 PLASMA PROTEOMIC BIOMARKER SIGNATURE OF AGE PREDICTS HEALTH AND LIFE SPAN. OLDER AGE IS A STRONG SHARED RISK FACTOR FOR MANY CHRONIC DISEASES, AND THERE IS INCREASING INTEREST IN IDENTIFYING AGING BIOMARKERS. HERE, A PROTEOMIC ANALYSIS OF 1301 PLASMA PROTEINS WAS CONDUCTED IN 997 INDIVIDUALS BETWEEN 21 AND 102 YEARS OF AGE. WE IDENTIFIED 651 PROTEINS ASSOCIATED WITH AGE (506 OVER-REPRESENTED, 145 UNDERREPRESENTED WITH AGE). MEDIATION ANALYSIS SUGGESTED A ROLE FOR PARTIAL CIS-EPIGENETIC CONTROL OF PROTEIN EXPRESSION WITH AGE. OF THE AGE-ASSOCIATED PROTEINS, 33.5% AND 45.3%, WERE ASSOCIATED WITH MORTALITY AND MULTIMORBIDITY, RESPECTIVELY. THERE WAS ENRICHMENT OF PROTEINS ASSOCIATED WITH INFLAMMATION AND EXTRACELLULAR MATRIX AS WELL AS SENESCENCE-ASSOCIATED SECRETORY PROTEINS. A 76-PROTEIN PROTEOMIC AGE SIGNATURE PREDICTED ACCUMULATION OF CHRONIC DISEASES AND ALL-CAUSE MORTALITY. THESE DATA SUPPORT THE USE OF PROTEOMIC BIOMARKERS TO MONITOR AGING TRAJECTORIES AND TO IDENTIFY INDIVIDUALS AT HIGHER RISK OF DISEASE TO BE TARGETED FOR IN DEPTH DIAGNOSTIC PROCEDURES AND EARLY INTERVENTIONS. 2020 13 5887 29 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 14 1846 24 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 15 6911 18 [TWO GERMAN BIRTH COHORTS: GINIPLUS AND LISAPLUS]. NUMEROUS CHRONIC DISEASES IN CHILDHOOD AND ADULTHOOD HAVE THEIR ORIGINS IN PERINATAL LIFE AND ARE POTENTIALLY INFLUENCED BY TRANS-GENERATIONAL EPIGENETIC PROCESSES. THEREFORE, PROSPECTIVE BIRTH COHORTS CAN SUBSTANTIALLY CONTRIBUTE TO OUR KNOWLEDGE ABOUT THE ETIOLOGY OF DISEASES INCLUDING MODIFIABLE RISK FACTORS. THE TWO POPULATION-BASED GERMAN BIRTH COHORTS GINIPLUS AND LISAPLUS AIM TO DESCRIBE THE NATURAL COURSE OF CHRONIC DISEASES AND INTERMEDIATE PHENOTYPES IN CHILDHOOD AND ITS DETERMINANTS, AND TO IDENTIFY POTENTIAL GENETIC EFFECT MODIFICATIONS. IN THE MID-1990S, 5,991 (GINIPLUS) AND 3,097 (LISAPLUS) HEALTHY, TERM NEWBORNS WERE RECRUITED FOR LONG-TERM FOLLOW-UP IN FOUR REGIONS OF GERMANY. THE FOLLOW-UP RATE FOR THE FIRST 10 YEARS WAS ABOUT 55%. WE ANALYZED THE GROWTH AND DEVELOPMENT OF OVERWEIGHT, INFECTIONS AND ALLERGIC DISEASES, MENTAL AND ORAL HEALTH, METABOLIC AND INFLAMMATORY PARAMETERS AND THE ROLE OF POTENTIAL RISK FACTORS INCLUDING GENETICS. THE RESULTS OF THESE TWO BIRTH COHORTS SUBSTANTIALLY CONTRIBUTE TO THE CURRENT KNOWLEDGE ABOUT THE NATURAL COURSE OF THESE HEALTH PARAMETERS. THESE DATA WERE INCLUDED IN MANY INTERNATIONAL PROJECTS AND CONSORTIA FOR PURPOSES OF INTERNATIONAL COMPARISONS OF PREVALENCE AND CONSISTENCY OF FINDINGS, AND TO INCREASE THE POWER OF THE ANALYSES. 2012 16 3050 21 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 17 2645 37 EPIGENOMIC INDICATORS OF AGE IN AFRICAN AMERICANS. AGE IS A WELL-ESTABLISHED RISK FACTOR FOR CHRONIC DISEASES. HOWEVER, THE CELLULAR AND MOLECULAR CHANGES ASSOCIATED WITH AGING PROCESSES THAT ARE RELATED TO CHRONIC DISEASE INITIATION AND PROGRESSION ARE NOT WELL-UNDERSTOOD. THUS, THERE IS AN INCREASED NEED TO IDENTIFY NEW MARKERS OF CELLULAR AND MOLECULAR CHANGES THAT OCCUR DURING AGING PROCESSES. IN THIS STUDY, WE USE GENOME-WIDE DNA METHYLATION FROM 26,428 CPG SITES IN 13,877 GENES TO INVESTIGATE THE RELATIONSHIP BETWEEN AGE AND EPIGENETIC VARIATION IN THE PERIPHERAL BLOOD CELLS OF 972 AFRICAN AMERICAN ADULTS FROM THE GENETIC EPIDEMIOLOGY NETWORK OF ARTERIOPATHY (GENOA) STUDY (MEAN AGE=66.3 YEARS, RANGE=39-95). AGE WAS SIGNIFICANTLY ASSOCIATED WITH 7,601 (28.8%) CPG SITES AFTER BONFERRONI CORRECTION FOR ALPHA=0.05 (P<1.89X10(-6)). DUE TO THE EXTRAORDINARILY STRONG ASSOCIATIONS BETWEEN AGE AND MANY OF THE CPG SITES (>7,000 SITES WITH P-VALUES RANGING FROM 10(-6) TO 10(-43)), WE INVESTIGATED HOW WELL THE DNA METHYLATION MARKERS PREDICT AGE. WE FOUND THAT 2,095 (7.9%) CPG SITES WERE SIGNIFICANT PREDICTORS OF AGE AFTER BONFERRONI CORRECTION. THE TOP FIVE PRINCIPAL COMPONENTS OF THE 2,095 AGE-ASSOCIATED CPG SITES ACCOUNTED FOR 69.3% OF THE VARIABILITY IN THESE CPG SITES, AND THEY EXPLAINED 26.8% OF THE VARIATION IN AGE. THE ASSOCIATIONS BETWEEN METHYLATION MARKERS AND ADULT AGE ARE SO UBIQUITOUS AND STRONG THAT WE HYPOTHESIZE THAT DNA METHYLATION PATTERNS MAY BE AN IMPORTANT MEASURE OF CELLULAR AGING PROCESSES. GIVEN THE HIGHLY CORRELATED NATURE OF THE AGE-ASSOCIATED EPIGENOME (AS EVIDENCED BY THE PRINCIPAL COMPONENTS ANALYSIS), WHOLE PATHWAYS MAY BE REGULATED AS A CONSEQUENCE OF AGING. 2014 18 1598 28 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 19 2627 38 EPIGENOME-WIDE ASSOCIATION STUDY OF ADIPOSITY AND FUTURE RISK OF OBESITY-RELATED DISEASES. BACKGROUND: OBESITY IS AN ESTABLISHED RISK FACTOR FOR SEVERAL COMMON CHRONIC DISEASES SUCH AS BREAST AND COLORECTAL CANCER, METABOLIC AND CARDIOVASCULAR DISEASES; HOWEVER, THE BIOLOGICAL BASIS FOR THESE RELATIONSHIPS IS NOT FULLY UNDERSTOOD. TO EXPLORE THE ASSOCIATION OF OBESITY WITH THESE CONDITIONS, WE INVESTIGATED PERIPHERAL BLOOD LEUCOCYTE (PBL) DNA METHYLATION MARKERS FOR ADIPOSITY AND THEIR CONTRIBUTION TO RISK OF INCIDENT BREAST AND COLORECTAL CANCER AND MYOCARDIAL INFARCTION. METHODS: DNA METHYLATION PROFILES (ILLUMINA INFINIUM((R)) HUMANMETHYLATION450 BEADCHIP) FROM 1941 INDIVIDUALS FROM FOUR POPULATION-BASED EUROPEAN COHORTS WERE ANALYSED IN RELATION TO BODY MASS INDEX, WAIST CIRCUMFERENCE, WAIST-HIP AND WAIST-HEIGHT RATIO WITHIN A META-ANALYTICAL FRAMEWORK. IN A SUBSET OF THESE INDIVIDUALS, DATA ON GENOME-WIDE GENE EXPRESSION LEVEL, BIOMARKERS OF GLUCOSE AND LIPID METABOLISM WERE ALSO AVAILABLE. VALIDATION OF METHYLATION MARKERS ASSOCIATED WITH ALL ADIPOSITY MEASURES WAS PERFORMED IN 358 INDIVIDUALS. FINALLY, WE INVESTIGATED THE ASSOCIATION OF OBESITY-RELATED METHYLATION MARKS WITH BREAST, COLORECTAL CANCER AND MYOCARDIAL INFARCTION WITHIN RELEVANT SUBSETS OF THE DISCOVERY POPULATION. RESULTS: WE IDENTIFIED 40 CPG LOCI WITH METHYLATION LEVELS ASSOCIATED WITH AT LEAST ONE ADIPOSITY MEASURE. OF THESE, ONE CPG LOCUS (CG06500161) IN ABCG1 WAS ASSOCIATED WITH ALL FOUR ADIPOSITY MEASURES (P = 9.07X10(-)(8) TO 3.27X10(-18)) AND LOWER TRANSCRIPTIONAL ACTIVITY OF THE FULL-LENGTH ISOFORM OF ABCG1 (P = 6.00X10(-7)), HIGHER TRIGLYCERIDE LEVELS (P = 5.37X10(-)(9)) AND HIGHER TRIGLYCERIDES-TO-HDL CHOLESTEROL RATIO (P = 1.03X10(-10)). OF THE 40 INFORMATIVE AND OBESITY-RELATED CPG LOCI, TWO (IN IL2RB AND FGF18) WERE SIGNIFICANTLY ASSOCIATED WITH COLORECTAL CANCER (INVERSELY, P < 1.6X10(-3)) AND ONE INTERGENIC LOCUS ON CHROMOSOME 1 WAS INVERSELY ASSOCIATED WITH MYOCARDIAL INFARCTION (P < 1.25X10(-3)), INDEPENDENTLY OF OBESITY AND ESTABLISHED RISK FACTORS. CONCLUSION: OUR RESULTS SUGGEST THAT EPIGENETIC CHANGES, IN PARTICULAR ALTERED DNA METHYLATION PATTERNS, MAY BE AN INTERMEDIATE BIOMARKER AT THE INTERSECTION OF OBESITY AND OBESITY-RELATED DISEASES, AND COULD OFFER CLUES AS TO UNDERLYING BIOLOGICAL MECHANISMS. 2018 20 1607 28 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