1 4607 116 NEIGHBORHOOD ENVIRONMENT AND DNA METHYLATION: IMPLICATIONS FOR CARDIOVASCULAR DISEASE RISK. EXPOSURE TO CHRONIC STRESS SUCH AS LIVING IN DISADVANTAGED NEIGHBORHOODS HAS BEEN RELATED TO CARDIOVASCULAR DISEASE (CVD). CHRONIC STRESS MAY INCREASE THE RISK FOR CVD BY INCREASING LEVELS OF SYSTEMIC INFLAMMATION (E.G., HIGHER LEVELS OF PRO-INFLAMMATORY CYTOKINES). DIFFERENTIAL DNA METHYLATION OF INFLAMMATION-RELATED CANDIDATE GENES IS ALSO RELATED TO HIGHER RISK FOR CVD. THUS, THE PURPOSE OF THIS REVIEW WAS TO EXAMINE THE ASSOCIATION OF NEIGHBORHOOD DISADVANTAGE WITH DNA METHYLATION. A SEARCH OF LITERATURE WAS CONDUCTED USING SCOPUS, CINAHL, PUBMED, MEDLINE, AND EMBASE DATABASES. THE KEYWORDS NEIGHBORHOOD, NEIGHBORHOOD DISORDER, NEIGHBORHOOD CRIME, NEIGHBORHOOD VIOLENCE, NEIGHBORHOOD SAFETY, BUILT ENVIRONMENT, AND HOUSING VACANCY WERE COMBINED WITH THE KEYWORDS DNA METHYLATION AND EPIGENETICS. FIVE STUDIES WERE INCLUDED IN THIS REVIEW (N = 3 ADULT BLOOD SAMPLES AND N = 2 FETAL BLOOD SAMPLES). FOUR OF THE FIVE STUDIES REPORTED AN ASSOCIATION OF NEIGHBORHOOD SOCIOECONOMIC STATUS, SOCIAL ENVIRONMENT, AND CRIME WITH EITHER GLOBAL OR GENE-SPECIFIC DNA METHYLATION. ONLY TWO STUDIES EXAMINED THE ASSOCIATION OF NEIGHBORHOOD DISADVANTAGE WITH INFLAMMATION-RELATED CANDIDATE GENES. ONE OF THESE STUDIES FOUND A SIGNIFICANT ASSOCIATION OF NEIGHBORHOOD SOCIOECONOMIC DISADVANTAGE AND SOCIAL ENVIRONMENT WITH DNA METHYLATION IN INFLAMMATION-RELATED CANDIDATE GENES. THUS, DATA ARE LIMITED ON THE ASSOCIATION BETWEEN NEIGHBORHOOD DISADVANTAGE AND DNA METHYLATION OF INFLAMMATION-RELATED CANDIDATE GENES, AS WELL AS GENES IN OTHER POTENTIAL MECHANISTIC PATHWAYS INCLUDING PSYCHOSOCIAL STRESS, TOXIN RESPONSE, AND ADIPOSITY. FUTURE STUDIES SHOULD EXAMINE THESE ASSOCIATIONS AND THE POTENTIAL EPIGENETIC MECHANISMS BY WHICH NEIGHBORHOOD DISADVANTAGE INCREASES THE RISK FOR CVD. 2019 2 247 40 ADULTHOOD ASTHMA AS A CONSEQUENCE OF CHILDHOOD ADVERSITY: A SYSTEMATIC REVIEW OF EPIGENETICALLY AFFECTED GENES. THERE IS AN ACCUMULATING DATA THAT SHOWS RELATION BETWEEN CHILDHOOD ADVERSITY AND VULNERABILITY TO CHRONIC DISEASES AS WELL AS EPIGENETIC INFLUENCES THAT IN TURN GIVE RISE TO THESE DISEASES. ASTHMA IS ONE OF THE CHRONIC DISEASES THAT IS INFLUENCED FROM GENETIC REGULATION OF THE INFLAMMATORY BIOMOLECULES AND THEREFORE THE HYPOTHESIS IN THIS RESEARCH WAS CHILDHOOD ADVERSITY MIGHT HAVE CAUSED EPIGENETIC DIFFERENTIATION IN THE ASTHMA-RELATED GENES IN THE POPULATION WHO HAD CHILDHOOD TRAUMA. TO TEST THIS HYPOTHESIS, THE LITERATURE WAS SYSTEMATICALLY REVIEWED TO EXTRACT EPIGENETICALLY MODIFIED GENE DATA OF THE ADULTS WHO HAD CHILDHOOD ADVERSITY, AND AFFECTED GENES WERE FURTHER EVALUATED FOR THEIR ASSOCIATION WITH ASTHMA. PRISMA GUIDELINES WERE ADOPTED AND PUBMED AND GOOGLE SCHOLAR WERE INCLUDED IN THE SEARCHED DATABASES, TO EVALUATE EPIGENETIC MODIFICATIONS IN ASTHMA-RELATED GENES OF PHYSICALLY, EMOTIONALLY OR SEXUALLY ABUSED CHILDREN. AFTER RETRIEVING A TOTAL OF 5245 ARTICLES, 36 OF THEM WERE INCLUDED IN THE STUDY. SEVERAL GENES AND PATHWAYS THAT MAY CONTRIBUTE TO PATHOGENESIS OF ASTHMA DEVELOPMENT, INCREASED INFLAMMATION, OR RESPONSE TO ASTHMA TREATMENT WERE FOUND EPIGENETICALLY AFFECTED BY CHILDHOOD TRAUMAS. CHILDHOOD ADVERSITY, CAUSING EPIGENETIC CHANGES IN DNA, MAY LEAD TO ASTHMA DEVELOPMENT OR INFLUENCE THE COURSE OF THE DISEASE AND THEREFORE SHOULD BE TAKEN INTO ACCOUNT FOR THE PROLONGED HEALTH CONSEQUENCES. 2022 3 2677 33 EVALUATING THE CHALLENGES AND REPRODUCIBILITY OF STUDIES INVESTIGATING DNA METHYLATION SIGNATURES OF PSYCHOLOGICAL STRESS. PSYCHOLOGICAL STRESS CAN INCREASE THE RISK OF A WIDE RANGE OF NEGATIVE HEALTH OUTCOMES. STUDIES HAVE BEEN COMPLETED TO DETERMINE IF DNA METHYLATION CHANGES OCCUR IN THE HUMAN BRAIN BECAUSE OF STRESS AND ARE ASSOCIATED WITH LONG-TERM EFFECTS AND DISEASE, BUT RESULTS HAVE BEEN INCONSISTENT. HUMAN CANDIDATE GENE STUDIES (150) AND EPIGENOME-WIDE ASSOCIATION STUDIES (67) WERE SYSTEMATICALLY EVALUATED TO ASSESS HOW DNA METHYLATION IS IMPACTED BY STRESS DURING THE PRENATAL PERIOD, EARLY CHILDHOOD AND ADULTHOOD. THE ASSOCIATION BETWEEN DNA METHYLATION OF NR3C1 EXON 1F AND CHILD MALTREATMENT AND EARLY LIFE ADVERSITY WAS WELL DEMONSTRATED, BUT OTHER GENES DID NOT EXHIBIT A CLEAR ASSOCIATION. THE REPRODUCIBILITY OF INDIVIDUAL CPG SITES IN EPIGENOME-WIDE ASSOCIATION STUDIES WAS ALSO POOR. HOWEVER, BIOLOGICAL PATHWAYS, INCLUDING STRESS RESPONSE, BRAIN DEVELOPMENT AND IMMUNITY, HAVE BEEN CONSISTENTLY IDENTIFIED ACROSS DIFFERENT STRESSORS THROUGHOUT THE LIFE SPAN. FUTURE STUDIES WOULD BENEFIT FROM THE INCREASED SAMPLE SIZE, LONGITUDINAL DESIGN, STANDARDIZED METHODOLOGY, OPTIMAL QUALITY CONTROL, AND IMPROVED STATISTICAL PROCEDURES. 2022 4 2075 34 EPIGENETIC DIFFERENCES IN INFLAMMATION GENES OF MONOZYGOTIC TWINS ARE RELATED TO PARENT-CHILD EMOTIONAL AVAILABILITY AND HEALTH. THE INFLAMMATORY RESPONSE IS AN IMMUNE DEFENSE ENGAGED IMMEDIATELY AFTER INJURY OR INFECTION. CHRONIC INFLAMMATION CAN BE DELETERIOUS FOR VARIOUS HEALTH OUTCOMES AND IS CHARACTERIZED BY HIGH LEVELS OF PRO-INFLAMMATORY MARKERS SUCH AS C-REACTIVE PROTEIN (CRP), INTERLEUKIN 6 (IL-6), AND TUMOR NECROSIS FACTOR ALPHA (TNF-ALPHA). A LARGE BODY OF RESEARCH DEMONSTRATES THESE INFLAMMATORY MARKERS ARE RESPONSIVE TO STRESS AND QUALITY OF SOCIAL RELATIONSHIPS THROUGHOUT THE LIFESPAN. FOR EXAMPLE, THE QUALITY OF THE EARLY PARENTAL BOND PREDICTS VARIOUS HEALTH OUTCOMES AND MAY BE DRIVEN BY CHANGES IN IMMUNE FUNCTION. EPIGENETIC PROCESSES, SUCH AS DNA METHYLATION, MAY BE ONE MECHANISM BY WHICH EARLY SOCIAL EXPERIENCES SHAPE IMMUNE FUNCTIONING. THE PRESENT STUDY USED A MONOZYGOTIC TWIN DIFFERENCE DESIGN TO ASSESS IF MOTHER-REPORTED EMOTIONAL AVAILABILITY AT 1 YEAR AND 2.5 YEARS PREDICTED IMMUNE GENE METHYLATION AT 8 YEARS OF AGE. FURTHER, WE ASSESSED IF INFLAMMATION GENE METHYLATION WAS RELATED TO GENERAL HEALTH PROBLEMS (E.G. INFECTIONS, ALLERGIES, ETC.). WE FOUND THAT MOTHER-REPORTED EMOTIONAL AVAILABILITY AT 1 YEAR, BUT NOT 2.5 YEARS, WAS RELATED TO METHYLATION OF VARIOUS IMMUNE GENES IN MONOZYGOTIC TWINS. FURTHERMORE, TWIN PAIRS DISCORDANT IN HEALTH PROBLEMS HAVE MORE DIFFERENCE IN IMMUNE GENE METHYLATION COMPARED TO TWIN PAIRS CONCORDANT FOR HEALTH PROBLEMS, SUGGESTING THAT METHYLATION OF IMMUNE GENES MAY HAVE FUNCTIONAL CONSEQUENCES FOR GENERAL HEALTH. THESE RESULTS SUGGEST THAT THE EMOTIONAL COMPONENT OF ATTACHMENT QUALITY DURING INFANCY CONTRIBUTES TO IMMUNE EPIGENETIC PROFILES IN CHILDHOOD, WHICH MAY INFLUENCE GENERAL HEALTH. 2020 5 2093 35 EPIGENETIC EFFECTS FOLLOWING ACUTE AND CHRONIC EXERCISE IN CARDIOVASCULAR DISEASE: A SYSTEMATIC REVIEW. INTRODUCTION: ACUTE EXERCISE AND EXERCISE TRAINING MAY CONFER EPIGENETIC MODIFICATIONS IN HEALTHY SUBJECTS. EPIGENETIC EFFECTS AFTER EXERCISE HAVE BEEN SHOWED IN PATIENTS WITH CARDIOVASCULAR DISEASE. THE AIM OF THIS SYSTEMATIC REVIEW WAS TO SUMMARIZE THE EVIDENCE FROM AVAILABLE CLINICAL TRIALS THAT STUDY EPIGENETIC ADAPTATIONS AFTER EXERCISE IN PATIENTS WITH CARDIOVASCULAR DISEASE. METHODS: THE SEARCH STRATEGY WAS PERFORMED IN PUBMED AND CENTRAL DATABASES ON ARTICLES PUBLISHED UNTIL SEPTEMBER 2020. STUDIES WITH TITLES AND ABSTRACTS RELEVANT TO EXERCISE EPIGENETIC MODIFICATION APPLIED TO CARDIOVASCULAR PATIENTS WERE FULLY EXAMINED. INCLUSION AND EXCLUSION CRITERIA WERE UTILIZED FOR STUDIES SCREENING. QUALITY ASSESSMENT WITH PEDRO SCALE AND EVALUATION BY TWO INDEPENDENT REVIEWERS WAS PERFORMED. RESULTS: OF THE 1714 ARTICLES RETRIEVED, 88 ARTICLES WERE ASSESSED FOR ELIGIBILITY CRITERIA AND 8 ARTICLES MATCHED OUR SEARCH CRITERIA AND FINALLY INCLUDED IN THE SYSTEMATIC ANALYSIS. THE ACUTE EXERCISE EPIGENETIC (MIRNAS) EFFECTS WERE ASSESSED IN THREE STUDIES AND THE CHRONIC EXERCISE TRAINING EFFECTS (MIRNAS AND DNA METHYLATION) IN SIX STUDIES. THE RESULTS HAVE SHOWN THAT THERE IS POSSIBLY AN ACUTE SIGNIFICANT EXERCISE EFFECT ON EPIGENETIC TARGETS WHICH IS MORE EVIDENT AFTER CHRONIC EXERCISE TRAINING. CONCLUSIONS: BY THE PRESENT SYSTEMATIC REVIEW, WE PROVIDE PRELIMINARY EVIDENCE OF BENEFICIAL EPIGENETIC ADAPTATIONS FOLLOWING ACUTE AND CHRONIC EXERCISE IN PATIENTS WITH CARDIOVASCULAR DISEASE. MORE CONTROLLED STUDIES ARE NEEDED TO CONFIRM SUCH EVIDENCE. 2021 6 5748 39 SOCIAL AND PHYSICAL ENVIRONMENTS EARLY IN DEVELOPMENT PREDICT DNA METHYLATION OF INFLAMMATORY GENES IN YOUNG ADULTHOOD. CHRONIC INFLAMMATION CONTRIBUTES TO A WIDE RANGE OF HUMAN DISEASES, AND ENVIRONMENTS IN INFANCY AND CHILDHOOD ARE IMPORTANT DETERMINANTS OF INFLAMMATORY PHENOTYPES. THE UNDERLYING BIOLOGICAL MECHANISMS CONNECTING EARLY ENVIRONMENTS WITH THE REGULATION OF INFLAMMATION IN ADULTHOOD ARE NOT KNOWN, BUT EPIGENETIC PROCESSES ARE PLAUSIBLE CANDIDATES. WE TESTED THE HYPOTHESIS THAT PATTERNS OF DNA METHYLATION (DNAM) IN INFLAMMATORY GENES IN YOUNG ADULTHOOD WOULD BE PREDICTED BY EARLY LIFE NUTRITIONAL, MICROBIAL, AND PSYCHOSOCIAL EXPOSURES PREVIOUSLY ASSOCIATED WITH LEVELS OF INFLAMMATION. DATA COME FROM A POPULATION-BASED LONGITUDINAL BIRTH COHORT STUDY IN METROPOLITAN CEBU, THE PHILIPPINES, AND DNAM WAS CHARACTERIZED IN WHOLE BLOOD SAMPLES FROM 494 PARTICIPANTS (AGE 20-22 Y). ANALYSES FOCUSED ON PROBES IN 114 TARGET GENES INVOLVED IN THE REGULATION OF INFLAMMATION, AND WE IDENTIFIED 10 SITES ACROSS NINE GENES WHERE THE LEVEL OF DNAM WAS SIGNIFICANTLY PREDICTED BY THE FOLLOWING VARIABLES: HOUSEHOLD SOCIOECONOMIC STATUS IN CHILDHOOD, EXTENDED ABSENCE OF A PARENT IN CHILDHOOD, EXPOSURE TO ANIMAL FECES IN INFANCY, BIRTH IN THE DRY SEASON, OR DURATION OF EXCLUSIVE BREASTFEEDING. TO EVALUATE THE BIOLOGICAL SIGNIFICANCE OF THESE SITES, WE TESTED FOR ASSOCIATIONS WITH A PANEL OF INFLAMMATORY BIOMARKERS MEASURED IN PLASMA OBTAINED AT THE SAME AGE AS DNAM ASSESSMENT. THREE SITES PREDICTED ELEVATED INFLAMMATION, AND ONE SITE PREDICTED LOWER INFLAMMATION, CONSISTENT WITH THE INTERPRETATION THAT LEVELS OF DNAM AT THESE SITES ARE FUNCTIONALLY RELEVANT. THIS PATTERN OF RESULTS POINTS TOWARD DNAM AS A POTENTIALLY IMPORTANT BIOLOGICAL MECHANISM THROUGH WHICH DEVELOPMENTAL ENVIRONMENTS SHAPE INFLAMMATORY PHENOTYPES ACROSS THE LIFE COURSE. 2017 7 120 35 A SYSTEMATIC REVIEW OF CHILDHOOD MALTREATMENT AND DNA METHYLATION: CANDIDATE GENE AND EPIGENOME-WIDE APPROACHES. CHILDHOOD MALTREATMENT IS A MAJOR RISK FACTOR FOR CHRONIC AND SEVERE MENTAL AND PHYSICAL HEALTH PROBLEMS ACROSS THE LIFESPAN. INCREASING EVIDENCE SUPPORTS THE HYPOTHESIS THAT MALTREATMENT IS ASSOCIATED WITH EPIGENETIC CHANGES THAT MAY SUBSEQUENTLY SERVE AS MECHANISMS OF DISEASE. THE CURRENT REVIEW USES A SYSTEMATIC APPROACH TO IDENTIFY AND SUMMARIZE THE LITERATURE RELATED TO CHILDHOOD MALTREATMENT AND ALTERATIONS IN DNA METHYLATION IN HUMANS. A TOTAL OF 100 EMPIRICAL ARTICLES WERE IDENTIFIED IN OUR SYSTEMATIC REVIEW OF RESEARCH PUBLISHED PRIOR TO OR DURING MARCH 2020, INCLUDING STUDIES THAT FOCUSED ON CANDIDATE GENES AND STUDIES THAT LEVERAGED EPIGENOME-WIDE DATA IN BOTH CHILDREN AND ADULTS. THEMES ARISING FROM THE LITERATURE, INCLUDING CONSISTENT AND INCONSISTENT PATTERNS OF RESULTS, ARE PRESENTED. SEVERAL DIRECTIONS FOR FUTURE RESEARCH, INCLUDING IMPORTANT METHODOLOGICAL CONSIDERATIONS FOR FUTURE STUDY DESIGN, ARE DISCUSSED. TAKEN TOGETHER, THE LITERATURE ON CHILDHOOD MALTREATMENT AND DNA METHYLATION UNDERSCORES THE COMPLEXITY OF TRANSACTIONS BETWEEN THE ENVIRONMENT AND BIOLOGY ACROSS DEVELOPMENT. 2021 8 1516 33 DNA METHYLATION AS A BIOMARKER OF AGING IN EPIDEMIOLOGIC STUDIES. CANCER IS LARGELY AN AGING DISEASE. ACCELERATED BIOLOGICAL AGING MAY BE THE STRONGEST PREDICTOR OF CANCER AND OTHER CHRONIC DISEASE RISKS. IN THE ABSENCE OF RELIABLE AND QUANTIFIABLE BIOMARKERS OF AGING TO DATE, IT HAS LONG BEEN OBSERVED THAT TUMORIGENESIS SHARES DISTINCT EPIGENETIC ALTERATIONS WITH THE AGING PROCESS. RECENTLY, EPIGENETIC AGE ESTIMATES HAVE BEEN DEVELOPED BASED ON THE AVAILABILITY OF GENOME-WIDE DNA METHYLATION PROFILES, BY APPLYING IN THE PREDICTION FORMULA THE METHYLATION LEVEL AT A SUBSET OF HIGHLY PREDICTIVE METHYLATION SITES, CALLED EPIGENETIC CLOCK. THESE DNA METHYLATION AGE ESTIMATES HAVE PRODUCED REMARKABLY STRONG CORRELATIONS WITH CHRONOLOGICAL AGE, WITH A SMALL DEVIATION AND HIGH REPRODUCIBILITY ACROSS DIFFERENT AGE GROUPS AND STUDY POPULATIONS. MOREOVER, AN INCREASING NUMBER OF EPIDEMIOLOGIC STUDIES HAVE DEMONSTRATED AN INDEPENDENT ASSOCIATION OF DNA METHYLATION AGE OR THE EXTENT OF ACCELERATION WITH MORTALITY AND VARIOUS AGING-RELATED CONDITIONS, EVEN AFTER ACCOUNTING FOR DIFFERENCES IN CHRONOLOGICAL AGE AND OTHER RISK FACTORS. ALTHOUGH EPIGENETIC PROFILES ARE KNOWN TO BE TISSUE-SPECIFIC, BOTH TARGET TISSUE- AND MULTIPLE TISSUE-DERIVED ESTIMATES APPEAR TO PERFORM WELL TO CAPTURE WHAT IS THOUGHT TO BE THE CUMULATIVE EPIGENETIC DRIFT THAT REPRESENTS A MULTIFACTORIAL DEGENERATIVE PROCESS ACROSS TISSUES AND ORGANISMS. FURTHER REFINEMENT OF THE EPIGENETIC AGE ESTIMATES IS ANTICIPATED OVER TIME TO ACCOMMODATE A BETTER TECHNOLOGICAL COVERAGE OF THE METHYLOME AND A BETTER UNDERSTANDING OF THE BIOLOGY UNDERLYING PREDICTIVE REGIONS. EPIDEMIOLOGIC PRINCIPLES WILL REMAIN CRITICAL FOR THE EVALUATION OF RESEARCH FINDINGS INVOLVING, FOR EXAMPLE, DIFFERENT STUDY POPULATIONS, DESIGN, FOLLOW-UP TIME, AND QUALITY OF COVARIATE DATA. OVERALL, THE EPIGENETIC AGE ESTIMATES ARE AN EXCITING DEVELOPMENT WITH USEFUL IMPLICATIONS FOR BIOMEDICAL RESEARCH OF HEALTHY AGING AND DISEASE PREVENTION AND CONTROL. 2018 9 1014 30 CIGARETTE SMOKING AND DNA METHYLATION. DNA METHYLATION IS THE MOST STUDIED EPIGENETIC MODIFICATION, CAPABLE OF CONTROLLING GENE EXPRESSION IN THE CONTEXTS OF NORMAL TRAITS OR DISEASES. IT IS HIGHLY DYNAMIC DURING EARLY EMBRYOGENESIS AND REMAINS RELATIVELY STABLE THROUGHOUT LIFE, AND SUCH PATTERNS ARE INTRICATELY RELATED TO HUMAN DEVELOPMENT. DNA METHYLATION IS A QUANTITATIVE TRAIT DETERMINED BY A COMPLEX INTERPLAY OF GENETIC AND ENVIRONMENTAL FACTORS. GENETIC VARIANTS AT A SPECIFIC LOCUS CAN INFLUENCE BOTH REGIONAL AND DISTANT DNA METHYLATION. THE ENVIRONMENT CAN HAVE VARYING EFFECTS ON DNA METHYLATION DEPENDING ON WHEN THE EXPOSURE OCCURS, SUCH AS DURING PRENATAL LIFE OR DURING ADULTHOOD. IN PARTICULAR, CIGARETTE SMOKING IN THE CONTEXT OF BOTH CURRENT SMOKING AND PRENATAL EXPOSURE IS A STRONG MODIFIER OF DNA METHYLATION. EPIGENOME-WIDE ASSOCIATION STUDIES HAVE UNCOVERED CANDIDATE GENES ASSOCIATED WITH CIGARETTE SMOKING THAT HAVE BIOLOGICALLY RELEVANT FUNCTIONS IN THE ETIOLOGY OF SMOKING-RELATED DISEASES. AS SUCH, DNA METHYLATION IS A POTENTIAL MECHANISTIC LINK BETWEEN CURRENT SMOKING AND CANCER, AS WELL AS PRENATAL CIGARETTE-SMOKE EXPOSURE AND THE DEVELOPMENT OF ADULT CHRONIC DISEASES. 2013 10 6112 43 THE EPIGENETIC CLOCK AS A PREDICTOR OF DISEASE AND MORTALITY RISK: A SYSTEMATIC REVIEW AND META-ANALYSIS. BACKGROUND: AGEING IS ONE OF THE PRINCIPAL RISK FACTORS FOR MANY CHRONIC DISEASES. HOWEVER, THERE IS CONSIDERABLE BETWEEN-PERSON VARIATION IN THE RATE OF AGEING AND INDIVIDUAL DIFFERENCES IN THEIR SUSCEPTIBILITY TO DISEASE AND DEATH. EPIGENETIC MECHANISMS MAY PLAY A ROLE IN HUMAN AGEING, AND DNA METHYLATION AGE BIOMARKERS MAY BE GOOD PREDICTORS OF AGE-RELATED DISEASES AND MORTALITY RISK. THE AIMS OF THIS SYSTEMATIC REVIEW WERE TO IDENTIFY AND SYNTHESISE THE EVIDENCE FOR AN ASSOCIATION BETWEEN PERIPHERALLY MEASURED DNA METHYLATION AGE AND LONGEVITY, AGE-RELATED DISEASE, AND MORTALITY RISK. METHODS: A SYSTEMATIC SEARCH WAS CONDUCTED IN LINE WITH THE PREFERRED REPORTING ITEMS FOR SYSTEMATIC REVIEWS AND META-ANALYSES (PRISMA) GUIDELINES. USING RELEVANT SEARCH TERMS, MEDLINE, EMBASE, COCHRANE CENTRAL REGISTER OF CONTROLLED TRIALS, AND PSYCHINFO DATABASES WERE SEARCHED TO IDENTIFY ARTICLES MEETING THE INCLUSION CRITERIA. STUDIES WERE ASSESSED FOR BIAS USING JOANNA BRIGGS INSTITUTE CRITICAL APPRAISAL CHECKLISTS. DATA WAS EXTRACTED FROM STUDIES MEASURING AGE ACCELERATION AS A PREDICTOR OF AGE-RELATED DISEASES, MORTALITY OR LONGEVITY, AND THE FINDINGS FOR SIMILAR OUTCOMES COMPARED. USING REVIEW MANAGER 5.3 SOFTWARE, TWO META-ANALYSES (ONE PER EPIGENETIC CLOCK) WERE CONDUCTED ON STUDIES MEASURING ALL-CAUSE MORTALITY. RESULTS: TWENTY-THREE RELEVANT ARTICLES WERE IDENTIFIED, INCLUDING A TOTAL OF 41,607 PARTICIPANTS. FOUR STUDIES FOCUSED ON AGEING AND LONGEVITY, 11 ON AGE-RELATED DISEASE (CANCER, CARDIOVASCULAR DISEASE, AND DEMENTIA), AND 11 ON MORTALITY. THERE WAS SOME, ALTHOUGH INCONSISTENT, EVIDENCE FOR AN ASSOCIATION BETWEEN INCREASED DNA METHYLATION AGE AND RISK OF DISEASE. META-ANALYSES INDICATED THAT EACH 5-YEAR INCREASE IN DNA METHYLATION AGE WAS ASSOCIATED AN 8 TO 15% INCREASED RISK OF MORTALITY. CONCLUSION: DUE TO THE SMALL NUMBER OF STUDIES AND HETEROGENEITY IN STUDY DESIGN AND OUTCOMES, THE ASSOCIATION BETWEEN DNA METHYLATION AGE AND AGE-RELATED DISEASE AND LONGEVITY IS INCONCLUSIVE. INCREASED EPIGENETIC AGE WAS ASSOCIATED WITH MORTALITY RISK, BUT POSITIVE PUBLICATION BIAS NEEDS TO BE CONSIDERED. FURTHER RESEARCH IS NEEDED TO DETERMINE THE EXTENT TO WHICH DNA METHYLATION AGE CAN BE USED AS A CLINICAL BIOMARKER. 2019 11 1583 27 DNA METHYLATION PROFILES OF BLOOD CELLS ARE DISTINCT BETWEEN EARLY-ONSET OBESE AND CONTROL INDIVIDUALS. OBESITY IS A HIGHLY PREVALENT, CHRONIC DISORDER THAT HAS BEEN INCREASING IN INCIDENCE IN YOUNG PATIENTS. BOTH EPIGENETIC AND GENETIC ABERRATIONS MAY PLAY A ROLE IN THE PATHOGENESIS OF OBESITY. THEREFORE, IN-DEPTH EPIGENOMIC AND GENOMIC ANALYSES WILL ADVANCE OUR UNDERSTANDING OF THE DETAILED MOLECULAR MECHANISMS UNDERLYING OBESITY AND AID IN THE SELECTION OF POTENTIAL BIOMARKERS FOR OBESITY IN YOUTH. HERE, WE PERFORMED MICROARRAY-BASED DNA METHYLATION AND GENE EXPRESSION PROFILING OF PERIPHERAL WHITE BLOOD CELLS OBTAINED FROM SIX YOUNG, OBESE INDIVIDUALS AND SIX HEALTHY CONTROLS. WE OBSERVED THAT THE HIERARCHICAL CLUSTERING OF DNA METHYLATION, BUT NOT GENE EXPRESSION, CLEARLY SEGREGATES THE OBESE INDIVIDUALS FROM THE CONTROLS, SUGGESTING THAT THE METABOLIC DISTURBANCE THAT OCCURS AS A RESULT OF OBESITY AT A YOUNG AGE MAY AFFECT THE DNA METHYLATION OF PERIPHERAL BLOOD CELLS WITHOUT ACCOMPANYING TRANSCRIPTIONAL CHANGES. TO EXAMINE THE GENOME-WIDE DIFFERENCES IN THE DNA METHYLATION PROFILES OF YOUNG OBESE AND CONTROL INDIVIDUALS, WE IDENTIFIED DIFFERENTIALLY METHYLATED CPG SITES AND INVESTIGATED THEIR GENOMIC AND EPIGENOMIC CONTEXTS. THE ABERRANT DNA METHYLATION PATTERNS IN OBESE INDIVIDUALS CAN BE SUMMARIZED AS RELATIVE GAINS AND LOSSES OF DNA METHYLATION IN GENE PROMOTERS AND GENE BODIES, RESPECTIVELY. WE ALSO OBSERVED THAT THE CPG ISLANDS OF OBESE INDIVIDUALS ARE MORE SUSCEPTIBLE TO DNA METHYLATION COMPARED TO CONTROLS. OUR PILOT STUDY SUGGESTS THAT THE GENOME-WIDE ABERRANT DNA METHYLATION PATTERNS OF OBESE INDIVIDUALS MAY ADVANCE NOT ONLY OUR UNDERSTANDING OF THE EPIGENOMIC PATHOGENESIS BUT ALSO EARLY SCREENING OF OBESITY IN YOUTH. 2017 12 1599 32 DNA METHYLATION SIGNATURE OF CHILDHOOD CHRONIC PHYSICAL AGGRESSION IN T CELLS OF BOTH MEN AND WOMEN. BACKGROUND: HIGH FREQUENCY OF PHYSICAL AGGRESSION IS THE CENTRAL FEATURE OF SEVERE CONDUCT DISORDER AND IS ASSOCIATED WITH A WIDE RANGE OF SOCIAL, MENTAL AND PHYSICAL HEALTH PROBLEMS. WE HAVE PREVIOUSLY TESTED THE HYPOTHESIS THAT DIFFERENTIAL DNA METHYLATION SIGNATURES IN PERIPHERAL T CELLS ARE ASSOCIATED WITH A CHRONIC AGGRESSION TRAJECTORY IN MALES. DESPITE THE FACT THAT SEX DIFFERENCES APPEAR TO PLAY A PIVOTAL ROLE IN DETERMINING THE DEVELOPMENT, MAGNITUDE AND FREQUENCY OF AGGRESSION, MOST OF PREVIOUS STUDIES FOCUSED ON MALES, SO LITTLE IS KNOWN ABOUT FEMALE CHRONIC PHYSICAL AGGRESSION. WE THEREFORE TESTED HERE WHETHER OR NOT THERE IS A SIGNATURE OF PHYSICAL AGGRESSION IN FEMALE DNA METHYLATION AND, IF THERE IS, HOW IT RELATES TO THE SIGNATURE OBSERVED IN MALES. METHODOLOGY/PRINCIPAL FINDINGS: METHYLATION PROFILES WERE CREATED USING THE METHOD OF METHYLATED DNA IMMUNOPRECIPITATION (MEDIP) FOLLOWED BY MICROARRAY HYBRIDIZATION AND STATISTICAL AND BIOINFORMATIC ANALYSES ON T CELL DNA OBTAINED FROM ADULT WOMEN WHO WERE FOUND TO BE ON A CHRONIC PHYSICAL AGGRESSION TRAJECTORY (CPA) BETWEEN 6 AND 12 YEARS OF AGE COMPARED TO WOMEN WHO FOLLOWED A NORMAL PHYSICAL AGGRESSION TRAJECTORY. WE CONFIRMED THE EXISTENCE OF A WELL-DEFINED, GENOME-WIDE SIGNATURE OF DNA METHYLATION ASSOCIATED WITH CHRONIC PHYSICAL AGGRESSION IN THE PERIPHERAL T CELLS OF ADULT FEMALES THAT INCLUDES MANY OF THE GENES SIMILARLY ASSOCIATED WITH PHYSICAL AGGRESSION IN THE SAME CELL TYPES OF ADULT MALES. CONCLUSIONS: THIS STUDY IN A SMALL NUMBER OF WOMEN PRESENTS PRELIMINARY EVIDENCE FOR A GENOME-WIDE VARIATION IN PROMOTER DNA METHYLATION THAT ASSOCIATES WITH CPA IN WOMEN THAT WARRANT LARGER STUDIES FOR FURTHER VERIFICATION. A SIGNIFICANT PROPORTION OF THESE ASSOCIATIONS WERE PREVIOUSLY OBSERVED IN MEN WITH CPA SUPPORTING THE HYPOTHESIS THAT THE EPIGENETIC SIGNATURE OF EARLY LIFE AGGRESSION IN FEMALES IS COMPOSED OF A COMPONENT SPECIFIC TO FEMALES AND ANOTHER COMMON TO BOTH MALES AND FEMALES. 2014 13 6159 42 THE GENETICS AND EPIGENETICS OF FATIGUE. FATIGUE IS A COMMON SYMPTOM AND INCLUDES BOTH PHYSICAL AND MENTAL COMPONENTS. IT CAN BE ASSOCIATED WITH A VARIETY OF DIFFERENT SYNDROMES AND DISEASES, BUT IN MANY CASES IS NOT ASSOCIATED WITH OTHER COMORBID CONDITIONS. MOST HUMANS HAVE EXPERIENCED ACUTE FATIGUE IN RELATION TO DIFFERENT STRESSORS. ACUTE FATIGUE TYPICALLY DECREASES AS THE EFFECT OF THE TRIGGERING FACTOR IS REDUCED AND A NORMAL HOMEOSTATIC BALANCE IS RESTORED. FATIGUE THAT PERSISTS FOR 6 MONTHS OR MORE IS TERMED CHRONIC FATIGUE. CHRONIC FATIGUE (CF) IN COMBINATION WITH A MINIMUM OF 4 OF 8 SYMPTOMS AND THE ABSENCE OF DISEASES THAT COULD EXPLAIN THESE SYMPTOMS, CONSTITUTE THE CASE DEFINITION FOR CHRONIC FATIGUE SYNDROME. IN SPITE OF ITS PREVALENCE, THE BIOLOGY OF FATIGUE IS RELATIVELY POORLY UNDERSTOOD AND BIOLOGICAL MARKERS HAVE NOT YET BEEN IDENTIFIED. THIS LITERATURE SEARCH WAS PERFORMED IN PUBMED TO IDENTIFY RESEARCH ON THE GENETICS AND EPIGENETICS OF FATIGUE. PUBLICATIONS WERE INCLUDED IF FATIGUE WAS A MAJOR TOPIC AND THE TOPIC WAS COMBINED WITH GENETIC AND/OR EPIGENETIC MEASUREMENTS IN ADULT HUMANS. A TOTAL OF 40 PUBLICATIONS WERE IDENTIFIED. ALTHOUGH ALTERED FUNCTIONING IN THE HYPOTHALAMIC-PITUITARY-ADRENAL AXIS, THE SEROTONERGIC SYSTEM, AND ASSOCIATIONS WITH INFECTIOUS AGENTS HAVE BEEN IDENTIFIED, THE SEARCH FOR GENETIC OR EPIGENETIC MARKERS OF FATIGUE, EITHER IN THE CONTEXT OF CF OR CHRONIC FATIGUE SYNDROME (CFS) HAS BEEN RELATIVELY UNPRODUCTIVE OR, IN THE CASE OF EPIGENETICS, NONEXISTENT. ALTHOUGH SEVERAL STUDIES, BOTH HYPOTHESIS-TESTING AND HYPOTHESIS-GENERATING, HAVE BEEN PERFORMED TO SEARCH FOR BIOMARKERS, THEY HAVE MOSTLY BEEN UNDERPOWERED, RESTRICTED BY THE HETEROGENEITY OF THE PHENOTYPE, OR LIMITED BY AN UNSYSTEMATIC STUDY DESIGN. TO BE ABLE TO CONFIRM THE HYPOTHESIS THAT RISK FOR, OR LEVELS OF, FATIGUE ARE INFLUENCED BY THE GENETIC OR EPIGENETIC BACKGROUND OF AN INDIVIDUAL, STUDIES NEED TO BE BASED ON LARGER SAMPLE SIZES WITH A MORE CLEARLY DEFINED PHENOTYPE. STUDIES NEED TO FOCUS NOT ONLY ON THE INFLUENCE OF A SINGLE ASPECT SUCH AS SINGLE NUCLEOTIDE POLYMORPHISMS (SNPS) OR DIFFERENTIAL GENE EXPRESSION ON DISEASE RISK OR STATE, BUT ALSO ON THE SYSTEMS BIOLOGY BEHIND THE DISEASE IN COMBINATION WITH INFORMATION ON ENVIRONMENTAL INFLUENCES AND VALIDATION OF FINDINGS IN FUNCTIONAL STUDIES. 2010 14 6790 25 [DNA METHYLATION ANALYSIS IN ENVIRONMENTAL AND OCCUPATIONAL CANCER RESEARCH]. THE PRESENT PAPER REVIEWS RECENT LABORATORY METHODS AND EXPERIMENTAL EVIDENCE CONCERNING EPIGENETIC BIOMARKERS INVOLVED IN CARCINOGENESIS MECHANISMS. WE INTRODUCE DNA METHYLATION AND ITS ROLE IN GENE EXPRESSION CONTROL. DNA METHYLATION ANALYSIS MAY ALLOW TO IDENTIFY EARLY CHANGES LEADING TO CANCER AND OTHER CHRONIC DISEASES. WE DESCRIBE HERE STRATEGIES FOR LABORATORY ANALYSES AND THEIR POSSIBLE APPLICATIONS. WE EXAMINE RESULTS FROM RECENT EXPERIMENTAL STUDIES SUGGESTING THAT THE EFFECTS OF CERTAIN OCCUPATIONAL AGENTS ARE MEDIATED BY ALTERATIONS IN DNA METHYLATION. PLANNING AND CONDUCTING INVESTIGATIONS ON EXPOSED HUMAN SUBJECTS WILL ALLOW TO VERIFY WHETHER DNA METHYLATION CHANGES IDENTIFIED IN ANIMAL AND IN-VITRO STUDIES MAY BE USED AS EARLY-EFFECT AND SUSCEPTIBILITY BIOMARKERS. DNA METHYLATION ANALYSIS HAS THE POTENTIAL FOR FUTURE APPLICATIONS IN RISK ASSESSMENT AND PREVENTION PROGRAMS CONDUCTED ON SUBJECTS EXPOSED TO HUMAN CARCINOGENS. 2005 15 2047 35 EPIGENETIC CLOCKS MAY COME OUT OF RHYTHM-IMPLICATIONS FOR THE ESTIMATION OF CHRONOLOGICAL AGE IN FORENSIC CASEWORK. THERE IS A GROWING PERCEPTION THAT DNA METHYLATION MAY BE INFLUENCED BY EXOGENOUS AND ENDOGENOUS PARAMETERS. KNOWLEDGE OF THESE FACTORS IS OF GREAT RELEVANCE FOR THE INTERPRETATION OF DNA-METHYLATION DATA FOR THE ESTIMATION OF CHRONOLOGICAL AGE IN FORENSIC CASEWORK. WE PERFORMED A LITERATURE REVIEW TO IDENTIFY PARAMETERS, WHICH MIGHT BE OF RELEVANCE FOR THE PREDICTION OF CHRONOLOGICAL AGE BASED ON DNA METHYLATION. THE QUALITY OF AGE PREDICTIONS MIGHT PARTICULARLY BE INFLUENCED BY LIFETIME ADVERSITIES (CHRONIC STRESS, TRAUMA/POST-TRAUMATIC STRESS DISORDER (PTSD), VIOLENCE, LOW SOCIOECONOMIC STATUS/EDUCATION), CANCER, OBESITY AND RELATED DISEASES, INFECTIOUS DISEASES (ESPECIALLY HIV AND CYTOMEGALOVIRUS (CMV) INFECTIONS), SEX, ETHNICITY AND EXPOSURE TO TOXINS (ALCOHOL, SMOKING, AIR POLLUTION, PESTICIDES). SUCH FACTORS MAY ALTER THE DNA METHYLATION PATTERN AND MAY EXPLAIN THE PARTLY HIGH DEVIATIONS BETWEEN EPIGENETIC AGE AND CHRONOLOGICAL AGE IN SINGLE CASES (DESPITE OF LOW MEAN ABSOLUTE DEVIATIONS) THAT CAN ALSO BE OBSERVED WITH "EPIGENETIC CLOCKS" COMPRISING A HIGH NUMBER OF CPG SITES. SO FAR, ONLY FEW PUBLICATIONS DEALING WITH FORENSIC AGE ESTIMATION ADDRESS THESE CONFOUNDING FACTORS. FUTURE RESEARCH SHOULD FOCUS ON THE IDENTIFICATION OF FURTHER RELEVANT CONFOUNDING FACTORS AND THE DEVELOPMENT OF MODELS THAT ARE "ROBUST" AGAINST THE INFLUENCE OF SUCH BIOLOGICAL FACTORS BY SYSTEMATIC INVESTIGATIONS UNDER TARGETED INCLUSION OF DIVERSE AND DEFINED COHORTS. 2020 16 666 51 BLOOD-BASED DNA METHYLATION BIOMARKERS FOR TYPE 2 DIABETES: POTENTIAL FOR CLINICAL APPLICATIONS. TYPE 2 DIABETES (T2D) IS A LEADING CAUSE OF DEATH AND DISABILITY WORLDWIDE. IT IS A CHRONIC METABOLIC DISORDER THAT DEVELOPS DUE TO AN INTERPLAY OF GENETIC, LIFESTYLE, AND ENVIRONMENTAL FACTORS. THE BIOLOGICAL ONSET OF THE DISEASE OCCURS LONG BEFORE CLINICAL SYMPTOMS DEVELOP, THUS THE SEARCH FOR EARLY DIAGNOSTIC AND PROGNOSTIC BIOMARKERS, WHICH COULD FACILITATE INTERVENTION STRATEGIES TO PREVENT OR DELAY DISEASE PROGRESSION, HAS INCREASED CONSIDERABLY IN RECENT YEARS. EPIGENETIC MODIFICATIONS REPRESENT IMPORTANT LINKS BETWEEN GENETIC, ENVIRONMENTAL AND LIFESTYLE CUES AND INCREASING EVIDENCE IMPLICATE ALTERED EPIGENETIC MARKS SUCH AS DNA METHYLATION, THE MOST CHARACTERIZED AND WIDELY STUDIED EPIGENETIC MECHANISM, IN THE PATHOGENESIS OF T2D. THIS REVIEW PROVIDES AN UPDATE OF THE CURRENT STATUS OF DNA METHYLATION AS A BIOMARKER FOR T2D. FOUR DATABASES, SCOPUS, PUBMED, COCHRANE CENTRAL, AND GOOGLE SCHOLAR WERE SEARCHED FOR STUDIES INVESTIGATING DNA METHYLATION IN BLOOD. THIRTY-SEVEN STUDIES WERE IDENTIFIED, AND ARE SUMMARIZED WITH RESPECT TO POPULATION CHARACTERISTICS, BIOLOGICAL SOURCE, AND METHOD OF DNA METHYLATION QUANTIFICATION (GLOBAL, CANDIDATE GENE OR GENOME-WIDE). WE HIGHLIGHT THAT DIFFERENTIAL METHYLATION OF THE TCF7L2, KCNQ1, ABCG1, TXNIP, PHOSPHO1, SREBF1, SLC30A8, AND FTO GENES IN BLOOD ARE REPRODUCIBLY ASSOCIATED WITH T2D IN DIFFERENT POPULATION GROUPS. THESE GENES SHOULD BE PRIORITIZED AND REPLICATED IN LONGITUDINAL STUDIES ACROSS MORE POPULATIONS IN FUTURE STUDIES. FINALLY, WE DISCUSS THE LIMITATIONS FACED BY DNA METHYLATION STUDIES, WHICH INCLUDE INCLUDING INTERPATIENT VARIABILITY, CELLULAR HETEROGENEITY, AND LACK OF ACCOUNTING FOR STUDY CONFOUNDERS. THESE LIMITATIONS AND CHALLENGES MUST BE OVERCOME BEFORE THE IMPLEMENTATION OF BLOOD-BASED DNA METHYLATION BIOMARKERS INTO A CLINICAL SETTING. WE EMPHASIZE THE NEED FOR LONGITUDINAL PROSPECTIVE STUDIES TO SUPPORT THE ROBUSTNESS OF THE CURRENT FINDINGS OF THIS REVIEW. 2018 17 228 37 ADAPTATION OF THE HUMAN POPULATION TO THE ENVIRONMENT: CURRENT KNOWLEDGE, CLUES FROM CZECH CYTOGENETIC AND "OMICS" BIOMONITORING STUDIES AND POSSIBLE MECHANISMS. THE HUMAN POPULATION IS CONTINUALLY EXPOSED TO NUMEROUS HARMFUL ENVIRONMENTAL STRESSORS, CAUSING NEGATIVE HEALTH EFFECTS AND/OR DEREGULATION OF BIOMARKER LEVELS. HOWEVER, STUDIES REPORTING NO OR EVEN POSITIVE IMPACTS OF SOME STRESSORS ON HUMANS ARE ALSO SOMETIMES PUBLISHED. THE MAIN AIM OF THIS REVIEW IS TO PROVIDE A COMPREHENSIVE OVERVIEW OF THE LAST DECADE OF CZECH BIOMONITORING RESEARCH, CONCERNING THE EFFECT OF VARIOUS LEVELS OF AIR POLLUTION (BENZO[A]PYRENE) AND RADIATION (URANIUM, X-RAY EXAMINATION AND NATURAL RADON BACKGROUND), ON THE DIFFERENTLY EXPOSED POPULATION GROUPS. BECAUSE SOME RESULTS OBTAINED FROM CYTOGENETIC STUDIES WERE OPPOSITE THAN HYPOTHESIZED, WE HAVE SEARCHED FOR A MEANINGFUL INTERPRETATION IN GENOMIC/EPIGENETIC STUDIES. A DETAILED ANALYSIS OF OUR DATA SUPPORTED BY THE STUDIES OF OTHERS AND CURRENT EPIGENETIC KNOWLEDGE, LEADS TO A HYPOTHESIS OF THE VERSATILE MECHANISM OF ADAPTATION TO ENVIRONMENTAL STRESSORS VIA DNA METHYLATION SETTINGS WHICH MAY EVEN ORIGINATE IN PRENATAL DEVELOPMENT, AND HELP TO REDUCE THE RESULTING DNA DAMAGE LEVELS. THIS HYPOTHESIS IS FULLY IN AGREEMENT WITH UNEXPECTED DATA FROM OUR STUDIES (E.G. LOWER LEVELS OF DNA DAMAGE IN SUBJECTS FROM HIGHLY POLLUTED REGIONS THAN IN CONTROLS OR IN SUBJECTS EXPOSED REPEATEDLY TO A POLLUTANT THAN IN THOSE WITHOUT PREVIOUS EXPOSURE), AND IS ALSO SUPPORTED BY DIFFERENCES IN DNA METHYLATION PATTERNS IN GROUPS FROM REGIONS WITH VARIOUS LEVELS OF POLLUTION. IN LIGHT OF THE ADAPTATION HYPOTHESIS, THE FOLLOWING POINTS MAY BE SUGGESTED FOR FUTURE RESEARCH: (I) THE CHRONIC AND ACUTE EXPOSURE OF STUDY SUBJECTS SHOULD BE DISTINGUISHED; (II) THE EXPOSURE HISTORY SHOULD BE MAPPED INCLUDING PLACE OF RESIDENCE DURING THE LIFE AND PRENATAL DEVELOPMENT; (III) CHANGES OF EPIGENETIC MARKERS SHOULD BE MONITORED OVER TIME. IN SUMMARY, INVESTIGATION OF HUMAN ADAPTATION TO THE ENVIRONMENT, ONE OF THE MOST IMPORTANT PROCESSES OF SURVIVAL, IS A NEW CHALLENGE FOR FUTURE RESEARCH IN THE FIELD OF HUMAN BIOMONITORING THAT MAY CHANGE OUR VIEW ON THE RESULTS OF BIOMARKER ANALYSES AND POTENTIAL NEGATIVE HEALTH IMPACTS OF THE ENVIRONMENT. 2017 18 1203 44 COULD EPIGENETICS HELP EXPLAIN RACIAL DISPARITIES IN CHRONIC PAIN? AFRICAN AMERICANS DISPROPORTIONATELY SUFFER MORE SEVERE AND DEBILITATING MORBIDITY FROM CHRONIC PAIN THAN DO NON-HISPANIC WHITES. THESE DIFFERENCES MAY ARISE FROM DIFFERENTIAL EXPOSURE TO PSYCHOSOCIAL AND ENVIRONMENTAL FACTORS SUCH AS ADVERSE CHILDHOOD EXPERIENCES, RACIAL DISCRIMINATION, LOW SOCIOECONOMIC STATUS, AND DEPRESSION, ALL OF WHICH HAVE BEEN ASSOCIATED WITH CHRONIC STRESS AND CHRONIC PAIN. RACE, AS A SOCIAL CONSTRUCT, MAKES IT SUCH THAT AFRICAN AMERICANS ARE MORE LIKELY TO EXPERIENCE DIFFERENT EARLY LIFE CONDITIONS, WHICH MAY INDUCE EPIGENETIC CHANGES THAT SUSTAIN RACIAL DIFFERENCES IN CHRONIC PAIN. EPIGENETICS IS ONE MECHANISM BY WHICH ENVIRONMENTAL FACTORS SUCH AS CHILDHOOD STRESS, RACIAL DISCRIMINATION, ECONOMIC HARDSHIP, AND DEPRESSION CAN AFFECT GENE EXPRESSION WITHOUT ALTERING THE UNDERLYING GENETIC SEQUENCE. THIS ARTICLE PROVIDES A NARRATIVE REVIEW OF THE LITERATURE ON EPIGENETICS AS A MECHANISM BY WHICH DIFFERENTIAL ENVIRONMENTAL EXPOSURE COULD EXPLAIN RACIAL DIFFERENCES IN CHRONIC PAIN. MOST STUDIES OF EPIGENETIC CHANGES IN CHRONIC PAIN EXAMINE DNA METHYLATION. DNA METHYLATION IS ALTERED IN THE GLUCOCORTICOID (STRESS RESPONSE) RECEPTOR GENE, NR3C1, WHICH HAS BEEN ASSOCIATED WITH DEPRESSION, CHILDHOOD STRESS, LOW SOCIOECONOMIC STATUS, AND CHRONIC PAIN. SIMILARLY, DNA METHYLATION PATTERNS OF IMMUNE CYTOKINE GENES HAVE BEEN ASSOCIATED WITH CHRONIC STRESS STATES. THUS, DNA METHYLATION CHANGES MAY PLAY AN ESSENTIAL ROLE IN THE EPIGENETIC MODULATION OF CHRONIC PAIN IN DIFFERENT RACES WITH A HIGHER INCIDENCE OF EPIGENETIC ALTERATIONS CONTRIBUTING TO MORE SEVERE AND DISABLING CHRONIC PAIN IN AFRICAN AMERICANS. 2019 19 287 27 AGING AND CHRONIC SUN EXPOSURE CAUSE DISTINCT EPIGENETIC CHANGES IN HUMAN SKIN. EPIGENETIC CHANGES ARE WIDELY CONSIDERED TO PLAY AN IMPORTANT ROLE IN AGING, BUT EXPERIMENTAL EVIDENCE TO SUPPORT THIS HYPOTHESIS HAS BEEN SCARCE. WE HAVE USED ARRAY-BASED ANALYSIS TO DETERMINE GENOME-SCALE DNA METHYLATION PATTERNS FROM HUMAN SKIN SAMPLES AND TO INVESTIGATE THE EFFECTS OF AGING, CHRONIC SUN EXPOSURE, AND TISSUE VARIATION. OUR RESULTS REVEAL A HIGH DEGREE OF TISSUE SPECIFICITY IN THE METHYLATION PATTERNS AND ALSO SHOWED VERY LITTLE INTERINDIVIDUAL VARIATION WITHIN TISSUES. DATA STRATIFICATION BY AGE REVEALED THAT DNA FROM OLDER INDIVIDUALS WAS CHARACTERIZED BY A SPECIFIC HYPERMETHYLATION PATTERN AFFECTING LESS THAN 1% OF THE MARKERS ANALYZED. INTERESTINGLY, STRATIFICATION BY SUN EXPOSURE PRODUCED A FUNDAMENTALLY DIFFERENT PATTERN WITH A SIGNIFICANT TREND TOWARDS HYPOMETHYLATION. OUR RESULTS THUS IDENTIFY DEFINED AGE-RELATED DNA METHYLATION CHANGES AND SUGGEST THAT THESE ALTERATIONS MIGHT CONTRIBUTE TO THE PHENOTYPIC CHANGES ASSOCIATED WITH SKIN AGING. 2010 20 1971 34 EPIGENETIC ALTERATIONS ASSOCIATED WITH CHILDHOOD TRAUMA AND ADULT MENTAL HEALTH OUTCOMES: A SYSTEMATIC REVIEW. OBJECTIVES: MULTIPLE, CHRONIC AND REPEATED TRAUMA EXPOSURE IN CHILDHOOD IS ASSOCIATED WITH ADVERSE MENTAL HEALTH OUTCOMES IN ADULTHOOD. IN THIS PAPER WE SYNTHESISE THE LITERATURE ON EPIGENETIC MODIFICATIONS IN CHILDHOOD TRAUMA (CT) AND THE MEDIATING EFFECTS OF DIFFERENTIAL EPIGENETIC MECHANISMS ON THE ASSOCIATION BETWEEN CT AND THE LATER ONSET OF PSYCHIATRIC DISORDERS.METHODS: WE REVIEWED THE LITERATURE UP TO MARCH 2018 IN FOUR DATABASES: PUBMED, WEB OF SCIENCE, EBSCOHOST AND SCOPUS. NON-HUMAN STUDIES WERE EXCLUDED. ALL STUDIES INVESTIGATING CT EXPOSURE BOTH IN HEALTHY ADULTS (18 YEARS AND OLDER) AND ADULTS WITH PSYCHIATRIC DISORDERS WERE INCLUDED.RESULTS: THIRTY-SIX PUBLICATIONS WERE INCLUDED. FOR MOOD DISORDERS, METHYLATION OF THE GLUCOCORTICOID RECEPTOR NR3C1 GENE, SPECIFICALLY AT THE NGFI-A BINDING SITE IN EXON 1F, AND CORRELATION WITH CT WAS A ROBUST FINDING. SEVERAL STUDIES DOCUMENTED DIFFERENTIAL METHYLATION OF SLC6A4, BDNF, OXTR AND FKBP5 IN ASSOCIATION WITH CT. COMMON PATHWAYS IDENTIFIED INCLUDE NEURONAL FUNCTIONING AND MAINTENANCE, IMMUNE AND INFLAMMATORY PROCESSES, CHROMATIN AND HISTONE MODIFICATION, AND TRANSCRIPTION FACTOR BINDING.CONCLUSIONS: A VARIETY OF EPIGENETIC MEDIATORS THAT LIE ON A COMMON PATHWAY BETWEEN CT AND PSYCHIATRIC DISORDERS HAVE BEEN IDENTIFIED, ALTHOUGH LONGITUDINAL STUDIES AND CONSISTENCY IN METHODOLOGICAL APPROACH ARE NEEDED TO DISENTANGLE CAUSE AND EFFECT ASSOCIATIONS. 2020