1 974 144 CHRONIC OCCUPATIONAL EXPOSURE ENDURED BY TOBACCO FARMERS FROM BRAZIL AND ASSOCIATION WITH DNA DAMAGE. TOBACCO FARMING IS AN IMPORTANT ECONOMIC INCOME IN BRAZIL, ALTHOUGH IT HAS BEEN CHALLENGED AS REGARD THE OCCUPATIONAL EXPOSURE TO BOTH PESTICIDES AND NICOTINE ENDURED BY FARMERS. CHRONIC OCCUPATIONAL EXPOSURE TO COMPLEX MIXTURES CAN LEAD TO HEALTH HAZARDOUS. WE EXAMINED GENOMIC INSTABILITY AND EPIGENETIC CHANGES IN TOBACCO FARMERS OCCUPATIONALLY EXPOSED TO PESTICIDE MIXTURES AND NICOTINE AT TOBACCO FIELDS. DNA DAMAGE WAS ASSESSED BY ALKALINE COMET ASSAY IN BLOOD CELLS. GENOMIC DNA WAS ISOLATED, AND TELOMERE LENGTH WAS MEASURED USING QUANTITATIVE POLYMERASE CHAIN REACTION ASSAY. WE MEASURED 5-METHYL-2'-DEOXYCYTIDINE, A MARKER OF GLOBAL DNA METHYLATION, AND P16 PROMOTER METHYLATION. THE OXIDATIVE PROFILE WAS EVALUATED BY TROLOX EQUIVALENT ANTIOXIDANT CAPACITY AND LIPID PEROXIDATION (THIOBARBITURIC ACID REACTIVE SUBSTANCES) IN SERUM. EXPOSURE PARAMETERS, PLASMA COTININE AND INORGANIC ELEMENT LEVELS, WERE ALSO MEASURED. DNA DAMAGE WAS SIGNIFICANTLY ELEVATED FOR FARMERS IN RELATION TO UNEXPOSED GROUP (P < 0.001; MANN-WHITNEY TEST) AND POSITIVELY ASSOCIATED WITH YEARS OF EXPOSURE. INVERSE RELATIONSHIP BETWEEN DNA DAMAGE AND TOTAL EQUIVALENT ANTIOXIDANT ACTIVITY WAS DEMONSTRATED FOR EXPOSED AND UNEXPOSED GROUPS. EXPOSED GROUP SHOWED SIGNIFICANTLY SHORTER TELOMERES (P < 0.001; UNPAIRED T-TEST) AND DNA HYPOMETHYLATION (P < 0.001; UNPAIRED T-TEST), AS WELL AS P16 HYPERMETHYLATION (P = 0.003; MANN-WHITNEY TEST). LIPID PEROXIDATION WAS INCREASED FOR EXPOSED GROUP IN RELATION TO UNEXPOSED ONE (P = 0.02; MANN-WHITNEY TEST) AND PRESENTED A POSITIVE CORRELATION WITH GLOBAL DNA METHYLATION (P = 0.0264). FARMERS HAVE INCREASED PLASMA COTININE LEVELS (P < 0.001) AND INORGANIC ELEMENTS (PHOSPHORUS, SULPHUR AND CHLORINE) IN RELATION TO UNEXPOSED GROUP. ELEVATED OXIDATIVE STRESS LEVELS DUE TO CHRONIC OCCUPATIONAL PESTICIDE MIXTURES AND NICOTINE EXPOSURE IN TOBACCO FARMERS WERE ASSOCIATED WITH HIGHER DNA DAMAGE, SHORTER TELOMERES AND ALTERED DNA METHYLATION. TELOMERE-ACCELERATED ATTRITION DUE TO EXPOSURE MAY BE POTENTIAL INTERMEDIATE STEP BEFORE A DISEASE STATE. 2018 2 5722 41 SISTER CHROMATID EXCHANGE AND PROLIFERATIVE RATE INDEX IN THE LONGITUDINAL RISK ASSESSMENT OF OCCUPATIONAL EXPOSURE TO PESTICIDES. AT PRESENT, THERE ARE MORE THAN 1,000 CHEMICALS CLASSIFIED AS PESTICIDES AND MANY REPORTS HAVE SHOWN THAT SOME OF THEM HAVE GENOTOXIC PROPERTIES. IN THE PRESENT LONGITUDINAL STUDY, POSSIBLE GENETIC DAMAGE ON A POPULATION OF WORKERS OCCUPATIONALLY EXPOSED TO A MIXTURE OF PESTICIDES BY USING SISTER CHROMATID EXCHANGE (SCE) ANALYSIS HAS BEEN EVALUATED. AS AN ADDITIONAL CYTOGENETIC PARAMETER, THE PROPORTION OF LYMPHOCYTES THAT UNDERGO ONE, TWO OR THREE CELL DIVISIONS AS WELL AS PROLIFERATIVE RATE INDEX HAVE BEEN DETERMINED. THIS STUDY WAS PERFORMED ON THE EXPOSED GROUP OF WORKERS EMPLOYED IN PESTICIDE PRODUCTION, SIMULTANEOUSLY EXPOSED TO A COMPLEX MIXTURE OF PESTICIDES (ATRAZINE, ALACHLOR, CYANAZINE, 2,4-DICHLOROPHENOXYACETIC ACID, AND MALATHION). THE BLOOD SAMPLES OF THE EXPOSED SUBJECTS WERE COLLECTED IN THREE DIFFERENT PERIODS: BEFORE THE BEGINNING OF THE NEW PESTICIDE PRODUCTION PERIOD, AFTER 8 MONTHS OF EVERYDAY WORK IN THE PESTICIDE PRODUCTION, AND 8 MONTHS AFTER THE REMOVAL OF SUBJECTS OUT OF THE PRODUCTION. IN ALL THREE SAMPLINGS, THE MEAN VALUE OF SCE AND NUMBER OF CELLS WITH HIGH SISTER CHROMATID EXCHANGE FREQUENCY (HFC) IN THE EXPOSED GROUP WAS SIGNIFICANTLY HIGHER IN THE COMPARISON WITH THE CONTROL GROUP. THERE WERE NO DIFFERENCES IN THE PROLIFERATIVE RATE INDEX (PRI) BETWEEN THE CONTROL AND EXPOSED GROUP, REGARDLESS OF THE SAMPLING PERIOD. IN BOTH GROUPS EXAMINED, THE MAJORITY OF LYMPHOCYTES WERE FOUND IN THE SECOND CELL DIVISION, FOLLOWING CULTIVATION. THESE RESULTS SUGGEST THAT THE INCREASE IN THE NUMBER OF SCE FOUND IN THE EXPOSED SUBJECTS IS NOT THE RESULT OF EITHER CYTOTOXIC OR EPIGENETIC ACTION OF PESTICIDE MIXTURE, BUT CHRONIC OCCUPATIONAL EXPOSURE TO MIXTURE OF PESTICIDES. 2002 3 1573 39 DNA METHYLATION PATTERNS IN NEWBORNS EXPOSED TO TOBACCO IN UTERO. BACKGROUND: MATERNAL SMOKING DURING PREGNANCY IS A MAJOR RISK FACTOR FOR ADVERSE HEALTH OUTCOMES. THE MAIN OBJECTIVE OF THE STUDY WAS TO ASSESS THE IMPACT OF IN UTERO TOBACCO EXPOSURE ON DNA METHYLATION IN CHILDREN BORN AT TERM WITH APPROPRIATE WEIGHT AT BIRTH. METHODS: TWENTY MOTHER-NEWBORN DYADS, AFTER UNCOMPLICATED PREGNANCIES, IN THE ABSENCE OF PERINATAL ILLNESS WERE INCLUDED. ALL MOTHERS WERE HEALTHY WITH NO CARDIOVASCULAR RISK FACTORS, EXCEPT FOR THE ASSOCIATED RISKS AMONG THOSE MOTHERS WHO SMOKED. UMBILICAL CORD BLOOD AND MATERNAL PERIPHERAL VENOUS BLOOD WERE COLLECTED AND AN EPIGENOME-WIDE ASSOCIATION STUDY WAS PERFORMED USING A 450 K EPIGENOME-WIDE SCAN (ILLUMINA INFINIUM HUMANMETHYLATION 450BEADCHIP) WITH ADJUSTMENT TO NORMALIZE THE DNA METHYLATION FOR DATA CELL VARIABILITY IN WHOLE BLOOD. RESULTS: THE MATERNAL PLASMATIC COTININE LEVELS RANGED FROM 10.70-115.40 NG/ML IN THE EXPOSED GROUP TO 0-0.59 NG/ML IN THE NON-EXPOSED GROUP. AFTER ADJUSTING FOR MULTIPLE COMPARISONS IN 427102 PROBES, STATISTICALLY SIGNIFICANT DIFFERENCES FOR 31 CPG SITES, ASSOCIATED TO 25 GENES WERE OBSERVED. THERE WAS A GREATER THAN EXPECTED PROPORTION OF STATISTICALLY-SIGNIFICANT LOCI LOCATED IN CPG ISLANDS (FISHER'S EXACT TEST, P = 0.029) AND OF THOSE CPG ISLANDS, 90.3% EXHIBIT HIGHER METHYLATION LEVELS IN THE EXPOSED GROUP. THE MOST STRIKING AND SIGNIFICANT CPG SITE, CG05727225, IS LOCATED IN THE CHROMOSOME 11P15.4, WITHIN THE ADRENOMEDULLIN GENE. CONCLUSIONS: IN UTERO TOBACCO EXPOSURE, EVEN IN THE ABSENCE OF FETAL GROWTH RESTRICTION, MAY ALTER THE EPIGENOME, CONTRIBUTING TO GLOBAL DNA HYPOMETHYLATION. THEREFORE, DNA STATUS CAN BE USED AS A BIOMARKER OF PRENATAL INSULTS. CONSIDERING THE POSSIBILITY TO REVERSE EPIGENETIC MODIFICATIONS, A WINDOW OF OPPORTUNITY EXISTS TO CHANGE THE PROGRAMMED CHRONIC DISEASE. 2015 4 3954 38 LONG INTERSPERSED NUCLEAR ELEMENT-1 METHYLATION STATUS IN THE CIRCULATING DNA FROM BLOOD OF PATIENTS WITH MALIGNANT AND CHRONIC INFLAMMATORY LUNG DISEASES. ALONG WITH OTHER MALIGNANT DISEASES, LUNG CANCER ARISES FROM THE PRECANCEROUS LUNG TISSUE STATE. ABERRANT DNA METHYLATION (HYPERMETHYLATION OF CERTAIN GENES AND HYPOMETHYLATION OF RETROTRANSPOSONS) IS KNOWN AS ONE OF THE DRIVING FORCES OF MALIGNANT CELL TRANSFORMATION. EPIGENETIC CHANGES WERE SHOWN TO BE DETECTABLE IN DNA, CIRCULATING IN THE BLOOD (CIRDNA) OF CANCER PATIENTS, INDICATING THE POSSIBILITY TO USE THEM AS CANCER MARKERS. THE CURRENT STUDY IS THE FIRST TO COMPARE THE LONG INTERSPERSED NUCLEAR ELEMENT-1 (LINE-1) METHYLATION LEVEL IN THE BLOOD FROM LUNG CANCER PATIENTS BEFORE TREATMENT VERSUS DIFFERENT CONTROL GROUPS AS HEALTHY SUBJECTS, PATIENTS WITH BRONCHITIS AND PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). THE CONCENTRATION OF LINE-1 METHYLATED FRAGMENTS, REGION 1 (LINE-1 METHYLATED, LINE-1-MET) WAS ESTIMATED BY QUANTITATIVE METHYL-SPECIFIC PCR. THE TOTAL CONCENTRATION OF THE CIRCULATING LINE-1 COPIES WAS MEASURED BY QPCR SPECIFIC FOR LINE-1 REGION 2, WHICH WAS SELECTED DUE TO ITS CPG METHYLATION-INDEPENDENT SEQUENCE (LINE-1-IND). BOTH LINE-1 METHYLATION LEVEL AND LINE-1 METHYLATION INDEX (LINE-1-MET/LINE-1-IND RATIO) WAS DECREASED IN LUNG CANCER PATIENTS COMPARED WITH THE JOINT CONTROL GROUP (HEALTHY SUBJECTS + PATIENTS WITH BRONCHITIS + COPD PATIENTS) (MANN-WHITNEY U-TEST, P = 0.016). WE ALSO FOUND THAT THE TENDENCY OF LINE-1 METHYLATION INDEX DECREASES IN THE CIRDNA FROM LUNG CANCER PATIENTS VERSUS COPD PATIENTS (MANN-WHITNEY U-TEST, P = 0.07). OUR DATA INDICATE THAT THE QUANTITATIVE ANALYSIS OF THE LINE-1 METHYLATION LEVEL IN THE CIRDNA IS VALUABLE FOR DISCRIMINATION OF LUNG CANCER PATIENTS FROM PATIENTS WITH CHRONIC INFLAMMATORY LUNG DISEASES. 2021 5 5628 34 SEMEN ABNORMALITIES, SPERM DNA DAMAGE AND GLOBAL HYPERMETHYLATION IN HEALTH WORKERS OCCUPATIONALLY EXPOSED TO IONIZING RADIATION. BACKGROUND: CYTOGENETIC STUDIES HAVE DEMONSTRATED THAT LOW LEVELS OF CHRONIC RADIATION EXPOSURE CAN POTENTIALLY INCREASE THE FREQUENCY OF CHROMOSOMAL ABERRATIONS AND ANEUPLOIDY IN SOMATIC CELLS. EPIDEMIOLOGICAL STUDIES HAVE SHOWN THAT HEALTH WORKERS OCCUPATIONALLY EXPOSED TO IONIZING RADIATION BEAR AN INCREASED RISK OF HEMATOLOGICAL MALIGNANCIES. OBJECTIVES: TO FIND THE INFLUENCE OF OCCUPATIONAL RADIATION EXPOSURE ON SEMEN CHARACTERISTICS, INCLUDING GENETIC AND EPIGENETIC INTEGRITY OF SPERMATOZOA IN A CHRONICALLY EXPOSED POPULATION. METHODS: THIS CROSS SECTIONAL STUDY INCLUDED 134 MALE VOLUNTEERS OF WHICH 83 WERE OCCUPATIONALLY EXPOSED TO IONIZING RADIATION AND 51 WERE NON-EXPOSED CONTROL SUBJECTS. SEMEN CHARACTERISTICS, SPERM DNA FRAGMENTATION, ANEUPLOIDY AND INCIDENCE OF GLOBAL HYPERMETHYLATION IN THE SPERMATOZOA WERE DETERMINED AND COMPARED BETWEEN THE NON-EXPOSED AND THE EXPOSED GROUP. RESULTS: DIRECT COMPARISON OF THE SEMEN CHARACTERISTICS BETWEEN THE NON-EXPOSED AND THE EXPOSED POPULATION REVEALED SIGNIFICANT DIFFERENCES IN MOTILITY CHARACTERISTICS, VIABILITY, AND MORPHOLOGICAL ABNORMALITIES (P<0.05-0.0001). ALTHOUGH, THE LEVEL OF SPERM DNA FRAGMENTATION WAS SIGNIFICANTLY HIGHER IN THE EXPOSED GROUP AS COMPARED TO THE NON-EXPOSED GROUP (P<0.05-0.0001), THE INCIDENCE OF SPERM ANEUPLOIDY WAS NOT STATISTICALLY DIFFERENT BETWEEN THE TWO GROUPS. HOWEVER, A SIGNIFICANT NUMBER OF HYPERMETHYLATED SPERMATOZOA WERE OBSERVED IN THE EXPOSED GROUP IN COMPARISON TO NON-EXPOSED GROUP (P<0.05). CONCLUSIONS: WE PROVIDE THE FIRST EVIDENCE ON THE DETRIMENTAL EFFECTS OF OCCUPATIONAL RADIATION EXPOSURE ON FUNCTIONAL, GENETIC AND EPIGENETIC INTEGRITY OF SPERM IN HEALTH WORKERS. HOWEVER, FURTHER STUDIES ARE REQUIRED TO CONFIRM THE POTENTIAL DETRIMENTAL EFFECTS OF IONIZING RADIATION IN THESE SUBJECTS. 2013 6 3442 44 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 1497 34 DNA METHYLATION AGE IS ACCELERATED IN ALCOHOL DEPENDENCE. ALCOHOL DEPENDENCE (ALC) IS A CHRONIC, RELAPSING DISORDER THAT INCREASES THE BURDEN OF CHRONIC DISEASE AND SIGNIFICANTLY CONTRIBUTES TO NUMEROUS PREMATURE DEATHS EACH YEAR. PREVIOUS RESEARCH SUGGESTS THAT CHRONIC, HEAVY ALCOHOL CONSUMPTION IS ASSOCIATED WITH DIFFERENTIAL DNA METHYLATION PATTERNS. IN ADDITION, DNA METHYLATION LEVELS AT CERTAIN CPG SITES HAVE BEEN CORRELATED WITH AGE. WE USED AN EPIGENETIC CLOCK TO INVESTIGATE THE POTENTIAL ROLE OF EXCESSIVE ALCOHOL CONSUMPTION IN EPIGENETIC AGING. WE EXPLORED THIS QUESTION IN FIVE INDEPENDENT COHORTS, INCLUDING DNA METHYLATION DATA DERIVED FROM DATASETS FROM BLOOD (N = 129, N = 329), LIVER (N = 92, N = 49), AND POSTMORTEM PREFRONTAL CORTEX (N = 46). ONE BLOOD DATASET AND ONE LIVER TISSUE DATASET OF INDIVIDUALS WITH ALC EXHIBITED POSITIVE AGE ACCELERATION (P < 0.0001 AND P = 0.0069, RESPECTIVELY), WHEREAS THE OTHER BLOOD AND LIVER TISSUE DATASETS BOTH EXHIBITED TRENDS OF POSITIVE AGE ACCELERATION THAT WERE NOT SIGNIFICANT (P = 0.83 AND P = 0.57, RESPECTIVELY). PREFRONTAL CORTEX TISSUE EXHIBITED A TREND OF NEGATIVE AGE ACCELERATION (P = 0.19). THESE RESULTS SUGGEST THAT EXCESSIVE ALCOHOL CONSUMPTION MAY BE ASSOCIATED WITH EPIGENETIC AGING IN A TISSUE-SPECIFIC MANNER AND WARRANTS FURTHER INVESTIGATION USING MULTIPLE TISSUE SAMPLES FROM THE SAME INDIVIDUALS. 2018 8 6311 36 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 1537 28 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 10 2632 39 EPIGENOME-WIDE DNA METHYLATION AND PESTICIDE USE IN THE AGRICULTURAL LUNG HEALTH STUDY. BACKGROUND: PESTICIDE EXPOSURE IS ASSOCIATED WITH MANY LONG-TERM HEALTH OUTCOMES; THE POTENTIAL UNDERLYING MECHANISMS ARE NOT WELL ESTABLISHED FOR MOST ASSOCIATIONS. EPIGENETIC MODIFICATIONS, SUCH AS DNA METHYLATION, MAY CONTRIBUTE. INDIVIDUAL PESTICIDES MAY BE ASSOCIATED WITH SPECIFIC DNA METHYLATION PATTERNS BUT NO EPIGENOME-WIDE ASSOCIATION STUDY (EWAS) HAS EVALUATED METHYLATION IN RELATION TO INDIVIDUAL PESTICIDES. OBJECTIVES: WE CONDUCTED AN EWAS OF DNA METHYLATION IN RELATION TO SEVERAL PESTICIDE ACTIVE INGREDIENTS. METHODS: THE AGRICULTURAL LUNG HEALTH STUDY IS A CASE-CONTROL STUDY OF ASTHMA, NESTED WITHIN THE AGRICULTURAL HEALTH STUDY. WE ANALYZED BLOOD DNA METHYLATION MEASURED USING ILLUMINA'S EPIC ARRAY IN 1,170 MALE FARMERS OF EUROPEAN ANCESTRY. FOR PESTICIDES STILL ON THE MARKET AT BLOOD COLLECTION (2009-2013), WE EVALUATED NINE ACTIVE INGREDIENTS FOR WHICH AT LEAST 30 PARTICIPANTS REPORTED PAST AND CURRENT (WITHIN THE LAST 12 MONTHS) USE, AS WELL AS SEVEN BANNED ORGANOCHLORINES WITH AT LEAST 30 PARTICIPANTS REPORTING PAST USE. WE USED ROBUST LINEAR REGRESSION TO COMPARE METHYLATION AT INDIVIDUAL C-PHOSPHATE-G SITES (CPGS) AMONG USERS OF A SPECIFIC PESTICIDE TO NEVER USERS. RESULTS: USING FAMILY-WISE ERROR RATE (P < 9 X 10-8) OR FALSE-DISCOVERY RATE (FDR < 0.05), WE IDENTIFIED 162 DIFFERENTIALLY METHYLATED CPGS ACROSS 8 OF 9 CURRENTLY MARKETED ACTIVE INGREDIENTS (ACETOCHLOR, ATRAZINE, DICAMBA, GLYPHOSATE, MALATHION, METOLACHLOR, MESOTRIONE, AND PICLORAM) AND ONE BANNED ORGANOCHLORINE (HEPTACHLOR). DIFFERENTIALLY METHYLATED CPGS WERE UNIQUE TO EACH ACTIVE INGREDIENT, AND A DOSE-RESPONSE RELATIONSHIP WITH LIFETIME DAYS OF USE WAS OBSERVED FOR MOST. SIGNIFICANT CPGS WERE ENRICHED FOR TRANSCRIPTION MOTIFS AND 28% OF CPGS WERE ASSOCIATED WITH WHOLE BLOOD CIS-GENE EXPRESSION, SUPPORTING FUNCTIONAL EFFECTS OF FINDINGS. WE CORROBORATED A PREVIOUSLY REPORTED ASSOCIATION BETWEEN DICHLORODIPHENYLTRICHLOROETHANE (BANNED IN THE UNITED STATES IN 1972) AND EPIGENETIC AGE ACCELERATION. DISCUSSION: WE IDENTIFIED DIFFERENTIAL METHYLATION FOR SEVERAL ACTIVE INGREDIENTS IN MALE FARMERS OF EUROPEAN ANCESTRY. THESE MAY SERVE AS BIOMARKERS OF CHRONIC EXPOSURE AND COULD INFORM MECHANISMS OF LONG-TERM HEALTH OUTCOMES FROM PESTICIDE EXPOSURE. HTTPS://DOI.ORG/10.1289/EHP8928. 2021 11 143 30 ABERRANT DNA METHYLATION OF TWO TUMOR SUPPRESSOR GENES, P14(ARF) AND P15(INK4B), AFTER CHRONIC OCCUPATIONAL EXPOSURE TO LOW LEVEL OF BENZENE. BACKGROUND: EXPOSURE TO BENZENE WOULD BE ASSOCIATED WITH MANY DISEASES INCLUDING LEUKEMIA. EPIGENETIC ALTERATIONS SEEM TO BE AMONG THE MAIN MECHANISMS INVOLVED. OBJECTIVE: TO DETERMINE IF CHRONIC OCCUPATIONAL EXPOSURE TO LOW LEVEL OF BENZENE WOULD BE ASSOCIATED WITH DNA METHYLATION. METHODS: GLOBAL DNA METHYLATION AND PROMOTER-SPECIFIC METHYLATION OF THE TWO TUMOR SUPPRESSOR GENES, P14(ARF) AND P15(INK4B), WERE ASSESSED EMPLOYING METHYLATION-SPECIFIC PCR USING THE DNA EXTRACTED FROM 40 PETROCHEMICAL WORKERS EXPOSED TO AMBIENT BENZENE LEVELS OF <1 PPM, AND 31 OFFICE WORKERS NOT EXPOSED TO BENZENE OR ITS DERIVATIVES. RESULTS: WHILE AN INCREASE IN GLOBAL DNA METHYLATION OF 5% IN P14(ARF) (P=0.501) AND 28% IN P15(INK4B) (P=0.02) GENES WAS OBSERVED IN THE EXPOSED GROUP, NO HYPERMETHYLATION IN EITHER OF THE STUDIED GENES WAS OBSERVED IN THE UNEXPOSED GROUP. NO SIGNIFICANT ASSOCIATION WAS FOUND BETWEEN THE FREQUENCY OF ABERRANT METHYLATION AND EITHER OF AGE, WORK EXPERIENCE, AND SMOKING HABIT IN THE EXPOSED GROUP. CONCLUSION: CHRONIC OCCUPATIONAL EXPOSURE TO LOWER THAN THE PERMISSIBLE EXPOSURE LIMIT OF BENZENE MAY STILL RESULT IN DNA METHYLATION OF TUMOR SUPPRESSOR GENES THAT MAY ULTIMATELY LEAD TO DEVELOPMENT OF CANCER. 2018 12 1553 42 DNA METHYLATION LEVELS ASSOCIATED WITH RACE AND CHILDHOOD ASTHMA SEVERITY. OBJECTIVE: ASTHMA IS A COMMON CHRONIC CHILDHOOD DISEASE WORLDWIDE. SOCIOECONOMIC STATUS, GENETIC PREDISPOSITION AND ENVIRONMENTAL FACTORS CONTRIBUTE TO ITS INCIDENCE AND SEVERITY. A DISPROPORTIONATE NUMBER OF CHILDREN WITH ASTHMA ARE ECONOMICALLY DISADVANTAGED AND LIVE IN SUBSTANDARD HOUSING WITH POTENTIAL INDOOR ENVIRONMENTAL EXPOSURES SUCH AS COCKROACHES, DUST MITES, RODENTS AND MOLDS. THESE EXPOSURES MAY MANIFEST THROUGH EPIGENETIC MECHANISMS THAT CAN LEAD TO CHANGES IN RELEVANT GENE EXPRESSION. WE EXAMINED THE ASSOCIATION OF GLOBAL DNA METHYLATION LEVELS WITH SOCIOECONOMIC STATUS, ASTHMA SEVERITY AND RACE/ETHNICITY. METHODS: WE MEASURED GLOBAL DNA METHYLATION IN PERIPHERAL BLOOD OF CHILDREN WITH ASTHMA ENROLLED IN THE KANSAS CITY SAFE AND HEALTHY HOMES PROGRAM. INCLUSION CRITERIA INCLUDED RESIDING IN THE SAME HOME FOR A MINIMUM OF 4 DAYS PER WEEK AND TOTAL FAMILY INCOME OF LESS THAN 80% OF THE KANSAS CITY MEDIAN FAMILY INCOME. DNA METHYLATION LEVELS WERE QUANTIFIED BY AN IMMUNOASSAY THAT ASSESSED THE PERCENTAGE OF 5-METHYLCYTOSINE. RESULTS: OUR RESULTS INDICATE THAT OVERALL, AFRICAN AMERICAN CHILDREN HAD HIGHER LEVELS OF GLOBAL DNA METHYLATION THAN CHILDREN OF OTHER RACES/ETHNICITIES (P = 0.029). THIS DIFFERENCE WAS MORE PRONOUNCED WHEN SOCIOECONOMIC STATUS AND ASTHMA SEVERITY WERE COUPLED WITH RACE/ETHNICITY (P = 0.042) WHERE LOW-INCOME, AFRICAN AMERICAN CHILDREN WITH PERSISTENT ASTHMA HAD SIGNIFICANTLY ELEVATED METHYLATION LEVELS RELATIVE TO OTHER RACES/ETHNICITIES IN THE SAME CONTEXT (P = 0.006, HEDGES G = 1.14). CONCLUSION: OUR STUDY DEMONSTRATES A SIGNIFICANT INTERACTION EFFECT AMONG GLOBAL DNA METHYLATION LEVELS, ASTHMA SEVERITY, RACE/ETHNICITY, AND SOCIOECONOMIC STATUS. 2017 13 3387 30 HOMOCYSTEINE ASSOCIATED GENOMIC DNA HYPERMETHYLATION IN PATIENTS WITH CHRONIC ALCOHOLISM. HIGHER PLASMA HOMOCYSTEINE CONCENTRATIONS CAN INFLUENCE GENOMIC DNA METHYLATION IN PERIPHERAL BLOOD CELLS. IN THE PRESENT CONTROLLED STUDY WE OBSERVED A SIGNIFICANT INCREASE (10%) OF GENOMIC DNA METHYLATION IN PATIENTS WITH ALCOHOLISM (T = -3.16, DF = 158, P = 0.002) WHICH WAS SIGNIFICANTLY ASSOCIATED WITH THEIR ELEVATED HOMOCYSTEINE LEVELS (MULTIPLE LINEAR REGRESSION, P < 0.001). SINCE METHYLATION OF DNA IS AN IMPORTANT EPIGENETIC FACTOR IN REGULATION OF GENE EXPRESSION THESE FINDINGS MAY HAVE IMPORTANT IMPLICATIONS FOR A POSSIBLE SUBSEQUENT DERANGEMENT OF EPIGENETIC CONTROL THESE PATIENTS. 2004 14 6083 41 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 15 1450 35 DISAGREEMENT BETWEEN TWO COMMON BIOMARKERS OF GLOBAL DNA METHYLATION. BACKGROUND: THE QUANTIFICATION OF GLOBAL DNA METHYLATION HAS BEEN ESTABLISHED IN EPIGENETIC SCREENING. AS MORE PRACTICABLE ALTERNATIVES TO THE HPLC-BASED GOLD STANDARD, THE METHYLATION ANALYSIS OF CPG ISLANDS IN REPEATABLE ELEMENTS (LINE-1) AND THE LUMINOMETRIC METHYLATION ASSAY (LUMA) OF OVERALL 5-METHYLCYTOSINE CONTENT IN "CCGG" RECOGNITION SITES ARE MOST WIDELY USED. BOTH METHODS ARE APPLIED AS VIRTUALLY EQUIVALENT, DESPITE THE HINTS THAT THEIR RESULTS ONLY PARTLY AGREE. THIS TRIGGERED THE PRESENT AGREEMENT ASSESSMENTS. RESULTS: THREE DIFFERENT HUMAN CELL TYPES (CULTURED MCF7 AND SHSY5Y CELL LINES TREATED WITH DIFFERENT CHEMICAL MODULATORS OF DNA METHYLATION AND WHOLE BLOOD DRAWN FROM PAIN PATIENTS AND HEALTHY VOLUNTEERS) WERE SUBMITTED TO THE GLOBAL DNA METHYLATION ASSAYS EMPLOYING LINE-1 OR LUMA-BASED PYROSEQUENCING MEASUREMENTS. THE AGREEMENT BETWEEN THE TWO BIOASSAYS WAS ASSESSED USING GENERALLY ACCEPTED APPROACHES TO THE STATISTICS FOR LABORATORY METHOD COMPARISON STUDIES. ALTHOUGH GLOBAL DNA METHYLATION LEVELS MEASURED BY THE TWO METHODS CORRELATED, FIVE DIFFERENT LINES OF STATISTICAL EVIDENCE CONSISTENTLY REJECTED THE ASSUMPTION OF COMPLETE AGREEMENT. SPECIFICALLY, A BIAS WAS OBSERVED BETWEEN THE TWO METHODS. IN ADDITION, BOTH THE MAGNITUDE AND DIRECTION OF BIAS WERE TISSUE-DEPENDENT. INTERASSAY DIFFERENCES COULD BE GROUPED BASED ON BAYESIAN STATISTICS, AND THESE GROUPS ALLOWED IN TURN TO RE-IDENTIFY THE ORIGINATING TISSUE. CONCLUSIONS: ALTHOUGH PROVIDING PARTLY CORRELATED MEASUREMENTS OF DNA METHYLATION, INTERCHANGEABILITY OF THE QUANTITATIVE RESULTS OBTAINED WITH LINE-1 AND LUMA WAS JEOPARDIZED BY A CONSISTENT BIAS BETWEEN THE RESULTS. MOREOVER, THE PRESENT ANALYSES STRONGLY INDICATE A TISSUE SPECIFICITY OF THE DIFFERENCES BETWEEN THE TWO METHODS. 2016 16 2921 40 GENE-SPECIFIC DIFFERENTIAL DNA METHYLATION AND CHRONIC ARSENIC EXPOSURE IN AN EPIGENOME-WIDE ASSOCIATION STUDY OF ADULTS IN BANGLADESH. BACKGROUND: INORGANIC ARSENIC IS ONE OF THE MOST COMMON NATURALLY OCCURRING CONTAMINANTS FOUND IN THE ENVIRONMENT. ARSENIC IS ASSOCIATED WITH A NUMBER OF HEALTH OUTCOMES, WITH EPIGENETIC MODIFICATION SUGGESTED AS A POTENTIAL MECHANISM OF TOXICITY. OBJECTIVE: AMONG A SAMPLE OF 400 ADULT PARTICIPANTS, WE EVALUATED THE ASSOCIATION BETWEEN ARSENIC EXPOSURE, AS MEASURED BY BLOOD AND URINARY TOTAL ARSENIC CONCENTRATIONS, AND EPIGENOME-WIDE WHITE BLOOD CELL DNA METHYLATION. METHODS: WE USED LINEAR REGRESSION MODELS TO EXAMINE THE ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND METHYLATION AT EACH CPG SITE, ADJUSTED FOR SEX, AGE, AND BATCH. DIFFERENTIALLY METHYLATED LOCI WERE SUBSEQUENTLY EXAMINED IN RELATION TO CORRESPONDING GENE EXPRESSION FOR FUNCTIONAL EVIDENCE OF GENE REGULATION. RESULTS: IN ADJUSTED ANALYSES, WE OBSERVED FOUR DIFFERENTIALLY METHYLATED CPG SITES WITH URINARY TOTAL ARSENIC CONCENTRATION AND THREE DIFFERENTIALLY METHYLATED CPG SITES WITH BLOOD ARSENIC CONCENTRATION, BASED ON THE BONFERRONI-CORRECTED SIGNIFICANCE THRESHOLD OF P < 1 X 10(-7). METHYLATION OF PLA2G2C (PROBE CG04605617) WAS THE MOST SIGNIFICANTLY ASSOCIATED LOCUS IN RELATION TO BOTH URINARY (P = 3.40 X 10(-11)) AND BLOOD ARSENIC CONCENTRATIONS (P = 1.48 X 10(-11)). THREE ADDITIONAL NOVEL METHYLATION LOCI-SQSTM1 (CG01225779), SLC4A4 (CG06121226), AND IGH (CG13651690)--WERE ALSO SIGNIFICANTLY ASSOCIATED WITH ARSENIC EXPOSURE. FURTHER, THERE WAS EVIDENCE OF METHYLATION-RELATED GENE REGULATION BASED ON GENE EXPRESSION FOR A SUBSET OF DIFFERENTIALLY METHYLATED LOCI. CONCLUSIONS: WE OBSERVED SIGNIFICANT ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND GENE-SPECIFIC DIFFERENTIAL WHITE BLOOD CELL DNA METHYLATION, SUGGESTING THAT EPIGENETIC MODIFICATIONS MAY BE AN IMPORTANT PATHWAY UNDERLYING ARSENIC TOXICITY. THE SPECIFIC DIFFERENTIALLY METHYLATED LOCI IDENTIFIED MAY INFORM POTENTIAL PATHWAYS FOR FUTURE INTERVENTIONS. 2015 17 6547 35 TRANSCRIPTOMICS OF LONG-TERM MEDITATION PRACTICE: EVIDENCE FOR PREVENTION OR REVERSAL OF STRESS EFFECTS HARMFUL TO HEALTH. BACKGROUND AND OBJECTIVES: STRESS CAN OVERLOAD ADAPTIVE MECHANISMS, LEADING TO EPIGENETIC EFFECTS HARMFUL TO HEALTH. RESEARCH ON THE REVERSAL OF THESE EFFECTS IS IN ITS INFANCY. EARLY RESULTS SUGGEST SOME MEDITATION TECHNIQUES HAVE HEALTH BENEFITS THAT GROW WITH REPEATED PRACTICE. THIS STUDY FOCUSED ON POSSIBLE TRANSCRIPTOMIC EFFECTS OF 38 YEARS OF TWICE-DAILY TRANSCENDENTAL MEDITATION((R)) (TM((R))) PRACTICE. MATERIALS AND METHODS: FIRST, USING ILLUMINA((R)) BEADCHIP MICROARRAY TECHNOLOGY, DIFFERENCES IN GLOBAL GENE EXPRESSION IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) WERE SOUGHT BETWEEN HEALTHY PRACTITIONERS AND TIGHTLY MATCHED CONTROLS (N = 12, AGE 65). SECOND, THESE MICROARRAY RESULTS WERE VERIFIED ON A SUBSET OF GENES USING QUANTITATIVE POLYMERASE CHAIN REACTION (QPCR) AND WERE VALIDATED USING QPCR IN LARGER TM AND CONTROL GROUPS (N = 45, AGE 63). BIOINFORMATICS INVESTIGATION EMPLOYED INGENUITY((R)) PATHWAY ANALYSIS (IPA((R))), DAVID, GENOMATIX, AND R PACKAGES. RESULTS: THE 200 GENES AND LOCI FOUND TO MEET STRICT CRITERIA FOR DIFFERENTIAL EXPRESSION IN THE MICROARRAY EXPERIMENT SHOWED CONTRASTING PATTERNS OF EXPRESSION THAT DISTINGUISHED THE TWO GROUPS. DIFFERENTIAL EXPRESSION RELATING TO IMMUNE FUNCTION AND ENERGY EFFICIENCY WERE MOST APPARENT. IN THE TM GROUP, RELATIVE TO THE CONTROL, ALL 49 GENES ASSOCIATED WITH INFLAMMATION WERE DOWNREGULATED, WHILE GENES ASSOCIATED WITH ANTIVIRAL AND ANTIBODY COMPONENTS OF THE DEFENSE RESPONSE WERE UPREGULATED. THE LARGEST EXPRESSION DIFFERENCES WERE SHOWN BY SIX GENES RELATED TO ERYTHROCYTE FUNCTION THAT APPEARED TO REFLECT A CONDITION OF LOWER ENERGY EFFICIENCY IN THE CONTROL GROUP. RESULTS SUPPORTING THESE GENE EXPRESSION DIFFERENCES WERE OBTAINED WITH QPCR-MEASURED EXPRESSION BOTH IN THE WELL-MATCHED MICROARRAY GROUPS AND IN THE LARGER, LESS WELL-MATCHED GROUPS. CONCLUSIONS: THESE FINDINGS ARE CONSISTENT WITH PREDICTIONS BASED ON RESULTS FROM EARLIER RANDOMIZED TRIALS OF MEDITATION AND MAY PROVIDE EVIDENCE FOR STRESS-RELATED MOLECULAR MECHANISMS UNDERLYING REDUCTIONS IN ANXIETY, POST-TRAUMATIC STRESS DISORDER (PTSD), CARDIOVASCULAR DISEASE (CVD), AND OTHER CHRONIC DISORDERS AND DISEASES. 2021 18 5957 33 TELOMERE LENGTH AND EPIGENETIC AGE ACCELERATION IN ADOLESCENTS WITH ANXIETY DISORDERS. EVIDENCE ON THE RELATIONSHIP BETWEEN GENETICS AND MENTAL HEALTH ARE FLOURISHING. HOWEVER, FEW STUDIES ARE EVALUATING EARLY BIOMARKERS THAT MIGHT LINK GENES, ENVIRONMENT, AND PSYCHOPATHOLOGY. WE AIMED TO STUDY TELOMERE LENGTH (TL) AND EPIGENETIC AGE ACCELERATION (AA) IN A COHORT OF ADOLESCENTS WITH AND WITHOUT ANXIETY DISORDERS (N = 234). WE EVALUATED A REPRESENTATIVE SUBSAMPLE OF PARTICIPANTS AT BASELINE AND AFTER 5 YEARS (N = 76) AND CATEGORIZED THEM ACCORDING TO THEIR ANXIETY DISORDER DIAGNOSIS AT BOTH TIME POINTS: (1) CONTROL GROUP (NO ANXIETY DISORDER, N = 18), (2) VARIABLE GROUP (ANXIETY DISORDER IN ONE EVALUATION, N = 38), AND (3) PERSISTENT GROUP (ANXIETY DISORDER AT BOTH TIME POINTS, N = 20). WE ASSESSED RELATIVE MEAN TL BY REAL-TIME QUANTITATIVE PCR AND DNA METHYLATION BY INFINIUM HUMANMETHYLATION450 BEADCHIP. WE CALCULATED AA USING THE HORVATH AGE ESTIMATION ALGORITHM AND ANALYZED DIFFERENCES AMONG GROUPS USING GENERALIZED LINEAR MIXED MODELS. THE PERSISTENT GROUP OF ANXIETY DISORDER DID NOT CHANGE TL OVER TIME (P = 0.495). THE VARIABLE GROUP HAD HIGHER BASELINE TL (P = 0.003) BUT NO ACCELERATED TL EROSION IN COMPARISON TO THE NON-ANXIETY CONTROL GROUP (P = 0.053). FURTHERMORE, THERE WERE NO DIFFERENCES IN AA AMONG GROUPS OVER TIME. OUR FINDINGS SUGGEST THAT ADOLESCENTS WITH CHRONIC ANXIETY DID NOT CHANGE TELOMERE LENGTH OVER TIME, WHICH COULD BE RELATED TO A DELAY IN NEURONAL DEVELOPMENT IN THIS PERIOD OF LIFE. 2021 19 816 31 CHARACTERISATION OF AN INFLAMMATION-RELATED EPIGENETIC SCORE AND ITS ASSOCIATION WITH COGNITIVE ABILITY. BACKGROUND: CHRONIC SYSTEMIC INFLAMMATION HAS BEEN ASSOCIATED WITH INCIDENT DEMENTIA, BUT ITS ASSOCIATION WITH AGE-RELATED COGNITIVE DECLINE IS LESS CLEAR. THE ACUTE RESPONSES OF MANY INFLAMMATORY BIOMARKERS MEAN THEY MAY PROVIDE AN UNRELIABLE PICTURE OF THE CHRONICITY OF INFLAMMATION. RECENTLY, A LARGE-SCALE EPIGENOME-WIDE ASSOCIATION STUDY IDENTIFIED DNA METHYLATION CORRELATES OF C-REACTIVE PROTEIN (CRP)-A WIDELY USED ACUTE-PHASE INFLAMMATORY BIOMARKER. DNA METHYLATION IS THOUGHT TO BE RELATIVELY STABLE IN THE SHORT TERM, MARKING IT AS A POTENTIALLY USEFUL SIGNATURE OF EXPOSURE. METHODS: WE UTILISE A DNA METHYLATION-BASED SCORE FOR CRP AND INVESTIGATE ITS TRAJECTORIES WITH AGE, AND ASSOCIATIONS WITH COGNITIVE ABILITY IN COMPARISON WITH SERUM CRP AND A GENETIC CRP SCORE IN A LONGITUDINAL STUDY OF OLDER ADULTS (N = 889) AND A LARGE, CROSS-SECTIONAL COHORT (N = 7028). RESULTS: WE IDENTIFIED NO HOMOGENEOUS TRAJECTORIES OF SERUM CRP WITH AGE ACROSS THE COHORTS, WHEREAS THE EPIGENETIC CRP SCORE WAS CONSISTENTLY FOUND TO INCREASE WITH AGE (STANDARDISED BETA = 0.07 AND 0.01) AND TO DO SO MORE RAPIDLY IN MALES COMPARED TO FEMALES. ADDITIONALLY, THE EPIGENETIC CRP SCORE HAD HIGHER TEST-RETEST RELIABILITY COMPARED TO SERUM CRP, INDICATING ITS ENHANCED TEMPORAL STABILITY. HIGHER SERUM CRP WAS NOT FOUND TO BE ASSOCIATED WITH POORER COGNITIVE ABILITY (STANDARDISED BETA = - 0.08 AND - 0.05); HOWEVER, A CONSISTENT NEGATIVE ASSOCIATION WAS IDENTIFIED BETWEEN COGNITIVE ABILITY AND THE EPIGENETIC CRP SCORE IN BOTH COHORTS (STANDARDISED BETA = - 0.15 AND - 0.08). CONCLUSIONS: AN EPIGENETIC PROXY OF CRP MAY PROVIDE A MORE RELIABLE SIGNATURE OF CHRONIC INFLAMMATION, ALLOWING FOR MORE ACCURATE STRATIFICATION OF INDIVIDUALS, AND THUS CLEARER INFERENCE OF ASSOCIATIONS WITH INCIDENT HEALTH OUTCOMES. 2020 20 5330 36 PUTATIVE EPIGENETIC BIOMARKERS OF STRESS IN RED BLOOD CELLS OF CHICKENS REARED ACROSS DIFFERENT BIOMES. PRODUCTION ANIMALS ARE CONSTANTLY SUBJECTED TO EARLY ADVERSE ENVIRONMENTAL CONDITIONS THAT INFLUENCE THE ADULT PHENOTYPE AND PRODUCE EPIGENETIC EFFECTS. CPG DINUCLEOTIDE METHYLATION IN RED BLOOD CELLS (RBC) COULD BE A USEFUL EPIGENETIC BIOMARKER TO IDENTIFY ANIMALS SUBJECTED TO CHRONIC STRESS IN THE PRODUCTION ENVIRONMENT. HERE WE COMPARED A REDUCED FRACTION OF THE RBC METHYLOME OF CHICKENS EXPOSED TO SOCIAL ISOLATION TO NON-EXPOSED. THESE EXPERIMENTS WERE PERFORMED IN TWO DIFFERENT LOCATIONS: BRAZIL AND SWEDEN. THE AIM WAS TO IDENTIFY STRESS-ASSOCIATED DNA METHYLATION PROFILES IN RBC ACROSS THESE POPULATIONS, IN SPITE OF THE VARIABLE CONDITIONS TO WHICH BIRDS ARE EXPOSED IN EACH FACILITY AND THEIR DIFFERENT LINEAGES. BIRDS WERE INCREASINGLY EXPOSED TO A SOCIAL ISOLATION TREATMENT, COMBINED WITH FOOD AND WATER DEPRIVATION, AT RANDOM PERIODS OF THE DAY FROM WEEKS 1-4 AFTER HATCHING. WE THEN COLLECTED THE RBC DNA FROM INDIVIDUALS AND COMPARED A REDUCED FRACTION OF THEIR METHYLOME BETWEEN THE EXPERIMENTAL GROUPS USING TWO BIOINFORMATIC APPROACHES TO IDENTIFY DIFFERENTIALLY METHYLATED REGIONS (DMRS): ONE USING FIXED-SIZE WINDOWS AND ANOTHER THAT PRESELECTED DIFFERENTIAL PEAKS WITH MACS2. THREE LEVELS OF SIGNIFICANCE WERE USED (P 50%) OF SPECIFIC TRANSCRIPTION FACTOR BINDING SITES. THREE OVERLAPPING DMRS WERE FOUND BETWEEN THE BR AND SW POPULATION USING THE MOST RELAXED P-VALUE (P