1 5361 159 RECENT ADVANCES IN ARSENIC RESEARCH: SIGNIFICANCE OF DIFFERENTIAL SUSCEPTIBILITY AND SUSTAINABLE STRATEGIES FOR MITIGATION. ARSENIC CONTAMINATION IN DRINKING WATER AND ASSOCIATED ADVERSE OUTCOMES ARE ONE OF THE MAJOR HEALTH ISSUES IN MORE THAN 50 COUNTRIES WORLDWIDE. THE SCENARIO IS GETTING EVEN MORE DETRIMENTAL WITH INCREASING NUMBER OF AFFECTED PEOPLE AND NEWER SITES REPORTED FROM ALL OVER THE WORLD. APART FROM DRINKING WATER, THE PRESENCE OF ARSENIC HAS BEEN FOUND IN VARIOUS OTHER DIETARY SOURCES. CHRONIC ARSENIC TOXICITY AFFECTS MULTIPLE PHYSIOLOGICAL SYSTEMS AND MAY CAUSE MALIGNANCIES LEADING TO DEATH. EXPOSED INDIVIDUALS, RESIDING IN THE SAME AREA, DEVELOPED DIFFERENTIAL DERMATOLOGICAL LESION PHENOTYPES AND VARIED SUSCEPTIBILITY TOWARD VARIOUS OTHER ARSENIC-INDUCED DISEASE RISK, EVEN AFTER CONSUMING EQUIVALENT AMOUNT OF ARSENIC FROM THE SIMILAR SOURCE, OVER THE SAME DURATION OF TIME. RESEARCHES SO FAR INDICATE THAT DIFFERENTIAL SUSCEPTIBILITY PLAYS AN IMPORTANT ROLE IN ARSENIC-INDUCED DISEASE MANIFESTATION. IN THIS COMPREHENSIVE REVIEW, WE HAVE IDENTIFIED MAJOR POPULATION-BASED STUDIES OF THE LAST 20 YEARS, INDICATING POSSIBLE CAUSES OF DIFFERENTIAL SUSCEPTIBILITY EMPHASIZING ARSENIC METHYLATION CAPACITY, VARIATION IN HOST GENOME (SINGLE NUCLEOTIDE POLYMORPHISM), AND INDIVIDUAL EPIGENETIC PATTERN (DNA METHYLATION, HISTONE MODIFICATION, AND MIRNA EXPRESSION). HOLISTIC MULTIDISCIPLINARY STRATEGIES NEED TO BE IMPLEMENTED WITH FEW SUSTAINABLE YET COST-EFFECTIVE SOLUTIONS LIKE ALTERNATIVE WATER SOURCE, TREATMENT OF ARSENIC-CONTAMINATED WATER, NEW ADAPTATIONS IN IRRIGATION SYSTEM, SIMPLE MODIFICATIONS IN COOKING STRATEGY, AND DIETARY SUPPLEMENTATIONS TO COMBAT THIS MENACE. OUR REVIEW FOCUSES ON THE PRESENT PERSPECTIVES OF ARSENIC RESEARCH WITH SPECIAL EMPHASIS ON THE PROBABLE CAUSES OF DIFFERENTIAL SUSCEPTIBILITY TOWARD CHRONIC ARSENIC TOXICITY AND SUSTAINABLE REMEDIATION STRATEGIES. 2020 2 1917 42 ENVIRONMENTAL ARSENIC EXPOSURE: FROM GENETIC SUSCEPTIBILITY TO PATHOGENESIS. MORE THAN 200 MILLION PEOPLE IN 70 COUNTRIES ARE EXPOSED TO ARSENIC THROUGH DRINKING WATER. CHRONIC EXPOSURE TO THIS METALLOID HAS BEEN ASSOCIATED WITH THE ONSET OF MANY DISEASES, INCLUDING CANCER. EPIDEMIOLOGICAL EVIDENCE SUPPORTS ITS CARCINOGENIC POTENTIAL, HOWEVER, DETAILED MOLECULAR MECHANISMS REMAIN TO BE ELUCIDATED. DESPITE THE GLOBAL MAGNITUDE OF THIS PROBLEM, NOT ALL INDIVIDUALS FACE THE SAME RISK. SUSCEPTIBILITY TO THE TOXIC EFFECTS OF ARSENIC IS INFLUENCED BY ALTERATIONS IN GENES INVOLVED IN ARSENIC METABOLISM, AS WELL AS BIOLOGICAL FACTORS, SUCH AS AGE, GENDER AND NUTRITION. MOREOVER, CHRONIC ARSENIC EXPOSURE RESULTS IN SEVERAL GENOTOXIC AND EPIGENETIC ALTERATIONS TIGHTLY ASSOCIATED WITH THE ARSENIC BIOTRANSFORMATION PROCESS, RESULTING IN AN INCREASED CANCER RISK. IN THIS REVIEW, WE: 1) REVIEW THE ROLES OF INTER-INDIVIDUAL DNA-LEVEL VARIATIONS INFLUENCING THE SUSCEPTIBILITY TO ARSENIC-INDUCED CARCINOGENESIS; 2) DISCUSS THE CONTRIBUTION OF ARSENIC BIOTRANSFORMATION TO CANCER INITIATION; 3) PROVIDE INSIGHTS INTO EMERGING RESEARCH AREAS AND THE CHALLENGES IN THE FIELD; AND 4) COMPILE A RESOURCE OF PUBLICLY AVAILABLE ARSENIC-RELATED DNA-LEVEL VARIATIONS, TRANSCRIPTOME AND METHYLATION DATA. UNDERSTANDING THE MOLECULAR MECHANISMS OF ARSENIC EXPOSURE AND ITS SUBSEQUENT HEALTH EFFECTS WILL SUPPORT EFFORTS TO REDUCE THE WORLDWIDE HEALTH BURDEN AND ENCOURAGE THE DEVELOPMENT OF STRATEGIES FOR MANAGING ARSENIC-RELATED DISEASES IN THE ERA OF PERSONALIZED MEDICINE. 2018 3 3210 41 HEALTH EFFECTS ASSOCIATED WITH PRE- AND PERINATAL EXPOSURE TO ARSENIC. INORGANIC ARSENIC IS A WELL-ESTABLISHED HUMAN CARCINOGEN, ABLE TO INDUCE GENETIC AND EPIGENETIC ALTERATIONS. MORE THAN 200 MILLION PEOPLE WORLDWIDE ARE EXPOSED TO ARSENIC CONCENTRATIONS IN DRINKING WATER EXCEEDING THE RECOMMENDED WHO THRESHOLD (10MUG/L). ADDITIONALLY, CHRONIC EXPOSURE TO LEVELS BELOW THIS THRESHOLD IS KNOWN TO RESULT IN LONG-TERM HEALTH EFFECTS IN HUMANS. THE ARSENIC-RELATED HEALTH EFFECTS IN HUMANS ARE ASSOCIATED WITH ITS BIOTRANSFORMATION PROCESS, WHEREBY THE RESULTING METABOLITES CAN INDUCE MOLECULAR DAMAGE THAT ACCUMULATES OVER TIME. THE EFFECTS DERIVED FROM THESE ALTERATIONS INCLUDE GENOMIC INSTABILITY ASSOCIATED WITH OXIDATIVE DAMAGE, ALTERATION OF GENE EXPRESSION (INCLUDING CODING AND NON-CODING RNAS), GLOBAL AND LOCALIZED EPIGENETIC REPROGRAMMING, AND HISTONE POSTTRANSLATIONAL MODIFICATIONS. THESE ALTERATIONS DIRECTLY AFFECT MOLECULAR PATHWAYS INVOLVED IN THE ONSET AND PROGRESSION OF MANY CONDITIONS THAT CAN ARISE EVEN DECADES AFTER THE EXPOSURE OCCURS. IMPORTANTLY, ARSENIC METABOLITES GENERATED DURING ITS BIOTRANSFORMATION CAN ALSO PASS THROUGH THE PLACENTAL BARRIER, RESULTING IN FETAL EXPOSURE TO THIS CARCINOGEN AT SIMILAR LEVELS TO THOSE OF THE MOTHER. AS SUCH, MORE IMMEDIATE EFFECTS OF THE ARSENIC-INDUCED MOLECULAR DAMAGE CAN BE OBSERVED AS DETRIMENTAL EFFECTS ON FETAL DEVELOPMENT, PREGNANCY, AND BIRTH OUTCOMES. IN THIS REVIEW, WE FOCUS ON THE GENETIC AND EPIGENETIC DAMAGE ASSOCIATED WITH EXPOSURE TO LOW LEVELS OF ARSENIC, PARTICULARLY THOSE AFFECTING EARLY DEVELOPMENTAL STAGES. WE ALSO PRESENT HOW THESE ALTERATIONS OCCURRING DURING EARLY LIFE CAN IMPACT THE DEVELOPMENT OF CERTAIN DISEASES IN ADULT LIFE. 2021 4 2655 52 EPIMUTAGENESIS: A PROSPECTIVE MECHANISM TO REMEDIATE ARSENIC-INDUCED TOXICITY. ARSENIC TOXICITY IS A GLOBAL ISSUE, ADDRESSED BY THE WORLD HEALTH ORGANIZATION AS ONE OF THE MAJOR NATURAL CALAMITIES FACED BY HUMANS. MORE THAN 137 MILLION INDIVIDUALS IN 70 NATIONS ARE AFFECTED BY ARSENIC MAINLY THROUGH DRINKING WATER AND ALSO THROUGH DIET. CHRONIC ARSENIC EXPOSURE LEADS TO VARIOUS TYPES OF PATHO-PHYSIOLOGICAL END POINTS IN HUMANS INCLUDING CANCERS. ARSENIC, A XENOBIOTIC SUBSTANCE, IS BIOTRANSFORMED IN THE BODY TO ITS METHYLATED SPECIES BY USING THE PHYSIOLOGICAL S-ADENOSYL METHIONINE (SAM). SAM DICTATES METHYLATION STATUS OF THE GENOME AND ARSENIC METABOLISM LEADS TO DEPLETION OF SAM LEADING TO AN EPIGENETIC DISEQUILIBRIUM. SINCE EPIGENETICS IS ONE OF THE MAJOR PHENOMENON AT THE INTERFACE BETWEEN THE ENVIRONMENT AND HUMAN HEALTH IMPACT, ITS DISEQUILIBRIUM BY ARSENIC INFLICTS UPON THE CHROMATIN COMPACTION, GENE EXPRESSION, GENOMIC STABILITY AND A HOST OF BIOMOLECULAR INTERACTIONS, THE INTERACTOME WITHIN THE CELL. SINCE ARSENIC IS NOT MUTAGENIC BUT IS CARCINOGENIC IN NATURE, ARSENIC INDUCED EPIMUTAGENESIS HAS COME TO THE FOREFRONT SINCE IT DETERMINES THE TRANSCRIPTIONAL AND GENOMIC INTEGRITY OF THE CELL. ARSENIC TOXICITY BRINGS FORTH SEVERAL PATHOPHYSIOLOGICAL MANIFESTATIONS LIKE DERMATOLOGICAL NON-CANCEROUS, PRE-CANCEROUS AND CANCEROUS LESIONS, PERIPHERAL NEUROPATHY, DNA DAMAGE, RESPIRATORY DISORDERS AND CANCERS OF SEVERAL INTERNAL ORGANS. RECENTLY, SEVERAL DISEASES OF SIMILAR MANIFESTATIONS HAVE BEEN EXPLAINED WITH THE RELEVANT EPIGENETIC PERSPECTIVES REGARDING THE POSSIBLE MOLECULAR MECHANISM FOR THEIR ONSET. HENCE, IN THE CURRENT REVIEW, WE COMPREHENSIVELY TRY TO INTERCALATE THE INFORMATION ON ARSENIC-INDUCED EPIGENETIC ALTERATIONS OF DNA, HISTONES AND MICRORNA SO AS TO UNDERSTAND WHETHER THE ARSENIC-INDUCED TOXIC MANIFESTATIONS ARE BROUGHT ABOUT BY THE EPIGENETIC CHANGES. WE HIGHLIGHT THE NEED TO UNDERSTAND THE ASPECT OF EPIMUTAGENESIS AND SUBSEQUENT ALTERATIONS IN THE CELLULAR INTERACTOME DUE TO ARSENIC-INDUCED MOLECULAR CHANGES, WHICH MAY BE UTILIZED TO DEVELOP PUTATIVE THERAPEUTIC STRATEGIES TARGETING BOTH OXIDATIVE POTENTIAL AND EPIMUTAGENESIS IN HUMANS. 2015 5 396 33 AN UPDATE ON EPIGENETICS AND CHILDHOOD RESPIRATORY DISEASES. EPIGENETIC MECHANISMS, DEFINED AS CHANGES IN PHENOTYPE OR GENE EXPRESSION CAUSED BY MECHANISMS OTHER THAN CHANGES IN THE UNDERLYING DNA SEQUENCE, HAVE BEEN PROPOSED TO CONSTITUTE A LINK BETWEEN GENETIC AND ENVIRONMENTAL FACTORS THAT AFFECT COMPLEX DISEASES. RECENT STUDIES SHOW THAT DNA METHYLATION, ONE OF THE KEY EPIGENETIC MECHANISMS, IS ALTERED IN CHILDREN EXPOSED TO AIR POLLUTANTS AND ENVIRONMENTAL TOBACCO SMOKE EARLY IN LIFE. SEVERAL CANDIDATE GENE STUDIES ON EPIGENETICS HAVE BEEN PUBLISHED TO DATE, BUT IT IS ONLY RECENTLY THAT GLOBAL METHYLATION ANALYSES HAVE BEEN PERFORMED FOR RESPIRATORY DISORDERS SUCH AS ASTHMA AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE. HOWEVER, LARGE-SCALE STUDIES WITH ADEQUATE POWER ARE YET TO BE PRESENTED IN CHILDREN, AND IMPLICATIONS FOR CLINICAL USE REMAIN TO BE EVALUATED. IN THIS REVIEW, WE SUMMARIZE THE RECENT ADVANCES IN EPIGENETICS AND RESPIRATORY DISORDERS IN CHILDREN, WITH A MAIN FOCUS ON METHODOLOGICAL CHALLENGES AND ANALYSES RELATED TO PHENOTYPE AND EXPOSURE USING GLOBAL METHYLATION APPROACHES. 2014 6 1928 41 ENVIRONMENTAL EXPOSURE MEASUREMENT IN CANCER EPIDEMIOLOGY. ENVIRONMENTAL EXPOSURES, USED IN THE BROADEST SENSE OF LIFESTYLE, INFECTIONS, RADIATION, NATURAL AND MAN-MADE CHEMICALS AND OCCUPATION, ARE A MAJOR CAUSE OF HUMAN CANCER. HOWEVER, THE PRECISE CONTRIBUTION OF SPECIFIC RISK FACTORS AND THEIR INTERACTION, BOTH WITH EACH OTHER AND WITH GENOTYPE, CONTINUES TO BE DIFFICULT TO ELUCIDATE. THIS IS PARTIALLY DUE TO LIMITATIONS IN ACCURATELY MEASURING EXPOSURE WITH THE SUBSEQUENT RISK OF MISCLASSIFICATION. ONE OF THE PRIMARY CHALLENGES OF MOLECULAR CANCER EPIDEMIOLOGY THEREFORE IS TO IMPROVE EXPOSURE ASSESSMENT. PROGRESS HAS BEEN MADE WITH BIOMARKERS SUCH AS CARCINOGENS AND THEIR METABOLITES, DNA AND PROTEIN ADDUCTS AND MUTATIONS MEASURED IN VARIOUS TISSUES AND BODY FLUIDS. NEVERTHELESS, MUCH REMAINS TO BE ACCOMPLISHED IN ORDER TO ESTABLISH AETIOLOGY AND PROVIDE THE EVIDENCE BASE FOR PUBLIC HEALTH DECISIONS. THIS REVIEW CONSIDERS SOME OF THE PRINCIPLES BEHIND THE APPLICATION OF EXPOSURE BIOMARKERS IN CANCER EPIDEMIOLOGY. IT ALSO DEMONSTRATES HOW THE SAME BIOMARKERS CAN CONTRIBUTE BOTH TO ESTABLISHING THE BIOLOGICAL PLAUSIBILITY OF ASSOCIATIONS BETWEEN EXPOSURE AND DISEASE AND BE VALUABLE ENDPOINTS IN INTERVENTION STUDIES. THE POTENTIAL OF NEW TECHNOLOGIES SUCH AS TRANSCRIPTOMICS, PROTEOMICS AND METABONOMICS TO PROVIDE A STEP CHANGE IN ENVIRONMENTAL EXPOSURE ASSESSMENT IS DISCUSSED. AN INCREASING RECOGNITION OF THE ROLE OF EPIGENETIC CHANGES IN CARCINOGENESIS PRESENTS A FRESH CHALLENGE AS ALTERATIONS IN DNA METHYLATION, HISTONE MODIFICATION AND MICRORNA IN RESPONSE TO ENVIRONMENTAL EXPOSURES DEMAND A NEW GENERATION OF EXPOSURE BIOMARKER. THE OVERALL IMPORTANCE OF THIS AREA OF RESEARCH IS BROUGHT INTO SHARP RELIEF BY THE LARGE PROSPECTIVE COHORT STUDIES (E.G. UK BIOBANK) WHICH NEED ACCURATE EXPOSURE MEASUREMENT IN ORDER TO SHED LIGHT ON THE COMPLEX GENE:ENVIRONMENT INTERACTIONS UNDERLYING COMMON CHRONIC DISORDERS INCLUDING CANCER. IT IS SUGGESTED THAT A CONCERTED EFFORT IS NOW REQUIRED, WITH APPROPRIATE FUNDING, TO DEVELOP AND VALIDATE THE REQUIRED EXPOSURE ASSESSMENT METHODOLOGY BEFORE THESE COHORTS COME TO MATURITY. 2009 7 2651 37 EPIGENOMICS AND TRANSCRIPTOMICS IN THE PREDICTION AND DIAGNOSIS OF CHILDHOOD ASTHMA: ARE WE THERE YET? ASTHMA IS THE MOST COMMON NON-COMMUNICABLE CHRONIC DISEASE OF CHILDHOOD. DESPITE ITS HIGH PREVALENCE, TO DATE WE LACK METHODS THAT ARE BOTH EFFICIENT AND ACCURATE IN DIAGNOSING ASTHMA. MOST TRADITIONAL APPROACHES HAVE BEEN BASED ON GARNERING CLINICAL EVIDENCE, SUCH AS RISK FACTORS AND EXPOSURES. GIVEN THE HIGH HERITABILITY OF ASTHMA, MORE RECENT APPROACHES HAVE LOOKED AT GENETIC POLYMORPHISMS AS POTENTIAL "RISK FACTORS." HOWEVER, GENETIC VARIANTS EXPLAIN ONLY A SMALL PROPORTION OF ASTHMA RISK, AND HAVE BEEN LESS THAN OPTIMAL AT PREDICTING RISK FOR INDIVIDUAL SUBJECTS. EPIGENOMIC STUDIES OFFER SIGNIFICANT ADVANTAGES OVER PREVIOUS APPROACHES. EPIGENETIC REGULATION IS HIGHLY TISSUE-SPECIFIC, AND CAN INDUCE BOTH SHORT- AND LONG-TERM CHANGES IN GENE EXPRESSION. SUCH CHANGES CAN START IN UTERO, CAN VARY THROUGHOUT THE LIFE SPAN, AND IN SOME INSTANCES CAN BE PASSED ON FROM ONE GENERATION TO ANOTHER. MOST IMPORTANTLY, THE EPIGENOME CAN BE MODIFIED BY ENVIRONMENTAL FACTORS AND EXPOSURES, AND THUS EPIGENETIC AND TRANSCRIPTOMIC PROFILING MAY YIELD THE MOST ACCURATE RISK ESTIMATES FOR A GIVEN PATIENT BY INCORPORATING ENVIRONMENTAL (AND TREATMENT) EFFECTS THROUGHOUT THE LIFESPAN. HERE WE WILL REVIEW THE MOST RECENT ADVANCES IN THE USE OF EPIGENETIC AND TRANSCRIPTOMIC ANALYSIS FOR THE EARLY DIAGNOSIS OF ASTHMA AND ATOPY, AS WELL AS CHALLENGES AND FUTURE DIRECTIONS IN THE FIELD AS IT MOVES FORWARD. WE WILL PARTICULARLY FOCUS ON DNA METHYLATION, THE MOST STUDIED MECHANISM OF EPIGENETIC REGULATION. 2019 8 6295 39 THE PROMISES AND CHALLENGES OF TOXICO-EPIGENOMICS: ENVIRONMENTAL CHEMICALS AND THEIR IMPACTS ON THE EPIGENOME. BACKGROUND: IT HAS BEEN ESTIMATED THAT A SUBSTANTIAL PORTION OF CHRONIC AND NONCOMMUNICABLE DISEASES CAN BE CAUSED OR EXACERBATED BY EXPOSURE TO ENVIRONMENTAL CHEMICALS. MULTIPLE LINES OF EVIDENCE INDICATE THAT EARLY LIFE EXPOSURE TO ENVIRONMENTAL CHEMICALS AT RELATIVELY LOW CONCENTRATIONS COULD HAVE LASTING EFFECTS ON INDIVIDUAL AND POPULATION HEALTH. ALTHOUGH THE POTENTIAL ADVERSE EFFECTS OF ENVIRONMENTAL CHEMICALS ARE KNOWN TO THE SCIENTIFIC COMMUNITY, REGULATORY AGENCIES, AND THE PUBLIC, LITTLE IS KNOWN ABOUT THE MECHANISTIC BASIS BY WHICH THESE CHEMICALS CAN INDUCE LONG-TERM OR TRANSGENERATIONAL EFFECTS. TO ADDRESS THIS QUESTION, EPIGENETIC MECHANISMS HAVE EMERGED AS THE POTENTIAL LINK BETWEEN GENETIC AND ENVIRONMENTAL FACTORS OF HEALTH AND DISEASE. OBJECTIVES: WE PRESENT AN OVERVIEW OF EPIGENETIC REGULATION AND A SUMMARY OF REPORTED EVIDENCE OF ENVIRONMENTAL TOXICANTS AS EPIGENETIC DISRUPTORS. WE ALSO DISCUSS THE ADVANTAGES AND CHALLENGES OF USING EPIGENETIC BIOMARKERS AS AN INDICATOR OF TOXICANT EXPOSURE, USING MEASURES THAT CAN BE TAKEN TO IMPROVE RISK ASSESSMENT, AND OUR PERSPECTIVES ON THE FUTURE ROLE OF EPIGENETICS IN TOXICOLOGY. DISCUSSION: UNTIL RECENTLY, EFFORTS TO APPLY EPIGENOMIC DATA IN TOXICOLOGY AND RISK ASSESSMENT WERE RESTRICTED BY AN INCOMPLETE UNDERSTANDING OF EPIGENOMIC VARIABILITY ACROSS TISSUE TYPES AND POPULATIONS. THIS IS POISED TO CHANGE WITH THE DEVELOPMENT OF NEW TOOLS AND CONCERTED EFFORTS BY RESEARCHERS ACROSS DISCIPLINES THAT HAVE LED TO A BETTER UNDERSTANDING OF EPIGENETIC MECHANISMS AND COMPREHENSIVE MAPS OF EPIGENOMIC VARIATION. WITH THE FOUNDATIONS NOW IN PLACE, WE FORESEE THAT UNPRECEDENTED ADVANCEMENTS WILL TAKE PLACE IN THE FIELD IN THE COMING YEARS. HTTPS://DOI.ORG/10.1289/EHP6104. 2020 9 1932 33 ENVIRONMENTAL EXPOSURES: AN UNDERRECOGNIZED CONTRIBUTION TO NONCOMMUNICABLE DISEASES. PREVIOUS ATTEMPTS TO DETERMINE THE DEGREE TO WHICH EXPOSURE TO ENVIRONMENTAL FACTORS CONTRIBUTE TO NONCOMMUNICABLE DISEASES (NCDS) HAVE BEEN VERY CONSERVATIVE AND HAVE SIGNIFICANTLY UNDERESTIMATED THE ACTUAL CONTRIBUTION OF THE ENVIRONMENT FOR AT LEAST TWO REASONS. FIRSTLY, MOST PREVIOUS REPORTS HAVE EXCLUDED THE CONTRIBUTION OF LIFESTYLE BEHAVIORAL RISK FACTORS, BUT THESE USUALLY INVOLVE SIGNIFICANT EXPOSURE TO ENVIRONMENTAL CHEMICALS THAT INCREASE RISK OF DISEASE. SECONDLY, EARLY LIFE EXPOSURE TO CHEMICAL CONTAMINANTS IS NOW CLEARLY ASSOCIATED WITH AN ELEVATED RISK OF SEVERAL DISEASES LATER IN LIFE, BUT THESE CONNECTIONS ARE OFTEN DIFFICULT TO DISCERN. THIS IS ESPECIALLY TRUE FOR ASTHMA AND NEURODEVELOPMENTAL CONDITIONS, BUT THERE IS ALSO A MAJOR CONTRIBUTION TO THE DEVELOPMENT OF OBESITY AND CHRONIC DISEASES. MOST CANCERS ARE CAUSED BY ENVIRONMENTAL EXPOSURES IN GENETICALLY SUSCEPTIBLE INDIVIDUALS. IN ADDITION, NEW INFORMATION SHOWS SIGNIFICANT ASSOCIATIONS BETWEEN CARDIOVASCULAR DISEASES AND DIABETES AND EXPOSURE TO ENVIRONMENTAL CHEMICALS PRESENT IN AIR, FOOD, AND WATER. THESE RELATIONSHIPS LIKELY REFLECT THE COMBINATION OF EPIGENETIC EFFECTS AND GENE INDUCTION. ENVIRONMENTAL FACTORS CONTRIBUTE SIGNIFICANTLY MORE TO NCDS THAN PREVIOUS REPORTS HAVE SUGGESTED. PREVENTION NEEDS TO SHIFT FOCUS FROM INDIVIDUAL RESPONSIBILITY TO SOCIETAL RESPONSIBILITY AND AN UNDERSTANDING THAT EFFECTIVE PREVENTION OF NCDS ULTIMATELY RELIES ON IMPROVED ENVIRONMENTAL MANAGEMENT TO REDUCE EXPOSURE TO MODIFIABLE RISKS. 2013 10 1041 48 CLINICAL AND MOLECULAR ASPECTS OF LEAD TOXICITY: AN UPDATE. LEAD TOXICITY IS A MAJOR PUBLIC HEALTH ISSUE IN DEVELOPED AND DEVELOPING COUNTRIES. BOTH ACUTE AND CHRONIC LEAD EXPOSURE HAS THE POTENTIAL TO CAUSE MANY DELETERIOUS SYSTEMATIC EFFECTS INCLUDING HYPERTENSION, FRANK ANEMIA, COGNITIVE DEFICITS, INFERTILITY, IMMUNE IMBALANCES, DELAYED SKELETAL AND DECIDUOUS DENTAL DEVELOPMENT, VITAMIN D DEFICIENCY, AND GASTROINTESTINAL EFFECTS. THE UNDERLYING MECHANISMS FOR ALL THESE SYSTEMIC EFFECTS HAVE NOT BEEN ELUCIDATED COMPLETELY. HOWEVER, THE MOST PLAUSIBLE CAUSE IS FREE RADICAL DAMAGE. IN ADDITION TO THIS, LEAD BEING A DIVALENT CATION CAN SURROGATE FOR CALCIUM AT MULTIPLE LEVELS AFFECTING VARIOUS CELL SIGNALING PATHWAYS. THE MOLECULAR BASIS OF LEAD EXPOSURE RESULTING IN VARIOUS SYSTEMIC EFFECTS IS BEING EXTENSIVELY EXPLORED. THE REPORTS INCLUDE SINGLE NUCLEOTIDE POLYMORPHISMS, EPIGENETIC MODIFICATIONS IN SUSCEPTIBLE INDIVIDUALS, AND THE MOST RECENT REPORTS ALSO FEATURE REGULATORY RNA MOLECULES - MIRNAS. HOWEVER, MANY GENETIC TARGETS ARE IDENTIFIED, BUT THEIR POSSIBLE MECHANISMS ARE STILL AN AREA TO BE EXPLORED. ADDITIONAL STUDIES ARE NEEDED IN DIFFERENT POPULATION GROUPS TO VALIDATE THE EXISTING FINDINGS, AS WELL AS TO FIND NEWER TARGETS THAT MAY HELP IN BETTER UNDERSTANDING THE MOLECULAR MECHANISMS CONTRIBUTING TO LEAD TOXICITY. FURTHERMORE, NEWER STRATEGIES FOR LEAD RISK ASSESSMENT BECOMES NECESSARY AS THE PREVIOUSLY RECOGNIZED "SAFE" LEVEL OF LEAD IS ALSO BEING FOUND TO BE ASSOCIATED WITH NEGATIVE HEALTH OUTCOMES. 2017 11 633 37 BIOLOGICAL EFFECTS AND EPIDEMIOLOGICAL CONSEQUENCES OF ARSENIC EXPOSURE, AND REAGENTS THAT CAN AMELIORATE ARSENIC DAMAGE IN VIVO. THROUGH CONTAMINATED DIET, WATER, AND OTHER FORMS OF ENVIRONMENTAL EXPOSURE, ARSENIC AFFECTS HUMAN HEALTH. THERE ARE MANY U.S. AND WORLDWIDE "HOT SPOTS" WHERE THE ARSENIC LEVEL IN PUBLIC WATER EXCEEDS THE MAXIMUM EXPOSURE LIMIT. THE BIOLOGICAL EFFECTS OF CHRONIC ARSENIC EXPOSURE INCLUDE GENERATION OF REACTIVE OXYGEN SPECIES (ROS), LEADING TO OXIDATIVE STRESS AND DNA DAMAGE, EPIGENETIC DNA MODIFICATION, INDUCTION OF GENOMIC INSTABILITY, AND INFLAMMATION AND IMMUNOMODULATION, ALL OF WHICH CAN INITIATE CARCINOGENESIS. HIGH ARSENIC EXPOSURE IS EPIDEMIOLOGICALLY ASSOCIATED WITH SKIN, LUNG, BLADDER, LIVER, KIDNEY AND PANCREATIC CANCER, AND CARDIOVASCULAR, NEURONAL, AND OTHER DISEASES. THIS REVIEW BRIEFLY SUMMARIZES THE BIOLOGICAL EFFECTS OF ARSENIC EXPOSURE AND EPIDEMIOLOGICAL CANCER STUDIES WORLDWIDE, AND PROVIDES AN OVERVIEW FOR EMERGING RODENT-BASED STUDIES OF REAGENTS THAT CAN AMELIORATE THE EFFECTS OF ARSENIC EXPOSURE IN VIVO. THESE REAGENTS MAY BE TRANSLATED TO HUMAN POPULATIONS FOR DISEASE PREVENTION. WE PROPOSE THE IMPORTANCE OF DEVELOPING A BIOMARKER-BASED PRECISION PREVENTION APPROACH FOR THE HEALTH ISSUES ASSOCIATED WITH ARSENIC EXPOSURE THAT AFFECTS MILLIONS OF PEOPLE WORLDWIDE. 2017 12 625 29 BIOLOGICAL AGE AND ENVIRONMENTAL RISK FACTORS FOR DEMENTIA AND STROKE: MOLECULAR MECHANISMS. SINCE THE DEVELOPMENT OF ANTIBIOTICS AND VACCINATION, AS WELL AS MAJOR IMPROVEMENTS IN PUBLIC HYGIENE, THE MAIN RISK FACTORS FOR MORBIDITY AND MORTALITY ARE AGE AND CHRONIC EXPOSURE TO ENVIRONMENTAL FACTORS, BOTH OF WHICH CAN INTERACT WITH GENETIC PREDISPOSITIONS. AS THE AVERAGE AGE OF THE POPULATION INCREASES, THE PREVALENCE AND COSTS OF CHRONIC DISEASES, ESPECIALLY NEUROLOGICAL CONDITIONS, ARE RAPIDLY INCREASING. THE DELETERIOUS EFFECTS OF AGE AND ENVIRONMENTAL RISK FACTORS, DEVELOP CHRONICALLY OVER RELATIVELY LONG PERIODS OF TIME, IN CONTRAST TO THE RELATIVELY RAPID DELETERIOUS EFFECTS OF INFECTIOUS DISEASES OR ACCIDENTS. OF PARTICULAR INTEREST IS THE HYPOTHESIS THAT THE DELETERIOUS EFFECTS OF ENVIRONMENTAL FACTORS MAY BE MEDIATED BY ACCELERATION OF BIOLOGICAL AGE. THIS HYPOTHESIS IS SUPPORTED BY EVIDENCE THAT DIETARY RESTRICTION, WHICH UNIVERSALLY DELAYS AGE-RELATED DISEASES, ALSO AMELIORATES DELETERIOUS EFFECTS OF ENVIRONMENTAL FACTORS. CONVERSELY, BOTH AGE AND ENVIRONMENTAL RISK FACTORS ARE ASSOCIATED WITH THE ACCUMULATION OF SOMATIC MUTATIONS IN MITOTIC CELLS AND EPIGENETIC MODIFICATIONS THAT ARE A MEASURE OF "BIOLOGICAL AGE", A BETTER PREDICTOR OF AGE-RELATED MORBIDITY AND MORTALITY THAN CHRONOLOGICAL AGE. HERE WE REVIEW EVIDENCE THAT ENVIRONMENTAL RISK FACTORS SUCH AS SMOKING AND AIR POLLUTION MAY ALSO DRIVE NEUROLOGICAL CONDITIONS, INCLUDING ALZHEIMER'S DISEASE, BY THE ACCELERATION OF BIOLOGICAL AGE, MEDIATED BY CUMULATIVE AND PERSISTENT EPIGENETIC EFFECTS AS WELL AS SOMATIC MUTATIONS. ELUCIDATION OF SUCH MECHANISMS COULD PLAUSIBLY ALLOW THE DEVELOPMENT OF INTERVENTIONS WHICH DELAY DELETERIOUS EFFECTS OF BOTH AGING AND ENVIRONMENTAL RISK FACTORS. 2022 13 2506 30 EPIGENETICS AND NUTRITION-RELATED EPIDEMICS OF METABOLIC DISEASES: CURRENT PERSPECTIVES AND CHALLENGES. WE LIVE IN A WORLD FASCINATED BY THE RELATIONSHIP BETWEEN DISEASE AND NUTRITIONAL DISEQUILIBRIUM. THE SUBTLE AND SLOW EFFECTS OF CHRONIC NUTRIENT TOXICITY ARE A MAJOR PUBLIC HEALTH CONCERN. SINCE FOOD IS POTENTIALLY IMPORTANT FOR THE DEVELOPMENT OF "METABOLIC MEMORY", THERE IS A NEED FOR MORE INFORMATION ON THE TYPE OF NUTRIENTS CAUSING ADVERSE OR TOXIC EFFECTS. WE NOW KNOW THAT METABOLIC ALTERATIONS PRODUCED BY EXCESSIVE INTAKE OF SOME NUTRIENTS, DRUGS AND CHEMICALS DIRECTLY IMPACT EPIGENETIC REGULATION. WE ENVISION THAT UNDERSTANDING HOW METABOLIC PATHWAYS ARE COORDINATED BY ENVIRONMENTAL AND GENETIC FACTORS WILL PROVIDE NOVEL INSIGHTS FOR THE TREATMENT OF METABOLIC DISEASES. NEW METHODS WILL ENABLE THE ASSEMBLY AND ANALYSIS OF LARGE SETS OF COMPLEX MOLECULAR AND CLINICAL DATA FOR UNDERSTANDING HOW INFLAMMATION AND MITOCHONDRIA AFFECT BIOENERGETICS, EPIGENETICS AND HEALTH. COLLECTIVELY, THE OBSERVATIONS WE HIGHLIGHT INDICATE THAT ENERGY UTILIZATION AND DISEASE ARE INTIMATELY CONNECTED BY EPIGENETICS. THE CHALLENGE IS TO INCORPORATE METABOLO-EPIGENETIC DATA IN BETTER INTERPRETATIONS OF DISEASE, TO EXPEDITE THERAPEUTIC TARGETING OF KEY PATHWAYS LINKING NUTRITIONAL TOXICITY AND METABOLISM. AN ADDITIONAL CONCERN IS THAT CHANGES IN THE PARENTAL PHENOTYPE ARE DETECTABLE IN THE METHYLOME OF SUBSEQUENT OFFSPRING. THE EFFECT MIGHT CREATE A MENACE TO FUTURE GENERATIONS AND PRECONCEPTIONAL CONSIDERATIONS. 2016 14 3775 35 INTERACTIONS BETWEEN ARSENIC-INDUCED TOXICITY AND NUTRITION IN EARLY LIFE. EXPOSURE TO ARSENIC THROUGH DRINKING WATER IS A MAJOR PUBLIC HEALTH PROBLEM AFFECTING MOST COUNTRIES, ALTHOUGH THE SITUATION IS PARTICULARLY SEVERE IN LOW-INCOME NATIONS. THE HEALTH CONSEQUENCES OF CHRONIC ARSENIC EXPOSURE INCLUDE INCREASED RISK FOR VARIOUS FORMS OF CANCER AND NUMEROUS NONCANCER EFFECTS, INCLUDING DIABETES, SKIN DISEASES, CHRONIC COUGH, AND TOXIC EFFECTS ON LIVER, KIDNEY, CARDIOVASCULAR SYSTEM, AND PERIPHERAL AND CENTRAL NERVOUS SYSTEMS. IN RECENT YEARS INCREASING REPORTS OF EFFECTS ON FETAL AND CHILD DEVELOPMENT HAVE APPEARED. THERE SEEMS TO BE A WIDE VARIATION IN SUSCEPTIBILITY TO ARSENIC TOXICITY, WHICH IS LIKELY TO BE RELATED TO FACTORS SUCH AS VARIATION IN ARSENIC METABOLISM, NUTRITION, HOST-RELATED DEFENSE MECHANISMS, AND GENETIC PREDISPOSITION. THE MAIN MECHANISMS OF ARSENIC-NUTRITION INTERACTIONS INCLUDE ARSENIC-INDUCED OXIDATIVE STRESS, WHICH REQUIRES NUTRIENT-DEPENDENT DEFENSE SYSTEMS, AND ARSENIC METABOLISM (METHYLATION) VIA 1-CARBON METABOLISM, WHICH REQUIRES METHYL GROUPS, FOLIC ACID, VITAMIN B-12, AND BETAINE FOR THE REMETHYLATION OF HOMOCYSTEINE TO METHIONINE. AN EFFICIENT FIRST METHYLATION STEP IN COMBINATION WITH A SLOW SECOND METHYLATION STEP SEEMS TO BE MOST CRITICAL FROM A TOXICOLOGICAL POINT OF VIEW. A THIRD MODE OF ARSENIC-NUTRITION INTERACTION INVOLVES EPIGENETIC EFFECTS AND FETAL PROGRAMMING VIA DNA METHYLATION. 2007 15 738 29 CANCER SUSCEPTIBILITY: EPIGENETIC MANIFESTATION OF ENVIRONMENTAL EXPOSURES. CANCER IS A DISEASE THAT RESULTS FROM BOTH GENETIC AND EPIGENETIC CHANGES. DISCORDANT PHENOTYPES AND VARYING INCIDENCES OF COMPLEX DISEASES SUCH AS CANCER IN MONOZYGOTIC TWINS AS WELL AS GENETICALLY IDENTICAL LABORATORY ANIMALS HAVE LONG BEEN ATTRIBUTED TO DIFFERENCES IN ENVIRONMENTAL EXPOSURES. ACCUMULATING EVIDENCE INDICATES, HOWEVER, THAT DISPARITIES IN GENE EXPRESSION RESULTING FROM VARIABLE MODIFICATIONS IN DNA METHYLATION AND CHROMATIN STRUCTURE IN RESPONSE TO THE ENVIRONMENT ALSO PLAY A ROLE IN DIFFERENTIAL SUSCEPTIBILITY TO DISEASE. DESPITE A GROWING CONSENSUS ON THE IMPORTANCE OF EPIGENETICS IN THE ETIOLOGY OF CHRONIC HUMAN DISEASES, THE GENES MOST PRONE TO EPIGENETIC DYSREGULATION ARE INCOMPLETELY DEFINED. MOREOVER, NEITHER THE ENVIRONMENTAL AGENTS MOST STRONGLY AFFECTING THE EPIGENOME NOR THE CRITICAL WINDOWS OF VULNERABILITY TO ENVIRONMENTALLY INDUCED EPIGENETIC ALTERATIONS ARE ADEQUATELY CHARACTERIZED. THESE MAJOR DEFICITS IN KNOWLEDGE MARKEDLY IMPAIR OUR ABILITY TO UNDERSTAND FULLY THE ETIOLOGY OF CANCER AND THE IMPORTANCE OF THE EPIGENOME IN DIAGNOSING AND PREVENTING THIS DEVASTATING DISEASE. 2007 16 3676 37 INFLAMMATION AND NEUTROPHIL IMMUNOSENESCENCE IN HEALTH AND DISEASE: TARGETED TREATMENTS TO IMPROVE CLINICAL OUTCOMES IN THE ELDERLY. DESPITE INCREASING LONGEVITY, MANY OLD PEOPLE ARE NOT IN GOOD HEALTH. THERE HAS BEEN AN INCREASE IN THE PREVALENCE OF AGE-ASSOCIATED MULTI-MORBIDITY (TWO OR MORE CHRONIC CONDITIONS IN THE SAME PERSON). ALSO, SEVERE INFECTIONS, SUCH AS PNEUMONIA, REMAIN SIGNIFICANT CAUSES OF MORTALITY AND MORBIDITY IN THIS AGING GROUP. MANY CHRONIC HEALTH CONDITIONS SHARE RISK FACTORS SUCH AS INCREASING AGE, SMOKING, A SEDENTARY LIFE STYLE AND BEING PART OF A LOWER SOCIOECONOMIC GROUP. HOWEVER, DESPITE THIS, MULTI-MORBIDITIES OFTEN CO-OCCUR MORE COMMONLY THAN WOULD BE PREDICTED. THIS HAS LED TO THE HYPOTHESIS THAT THEY SHARE COMMON UNDERLYING MECHANISMS. THIS IS AN IMPORTANT CONCEPT, FOR IF IT WERE TRUE, TREATMENTS COULD BE DEVISED WHICH TARGET THESE COMMON PATHWAYS AND IMPROVE A NUMBER OF AGE-ASSOCIATED HEALTH CONDITIONS. MANY CHRONIC ILLNESSES ASSOCIATED WITH MULTI-MORBIDITY AND SEVERE INFECTIONS ARE CHARACTERIZED BY AN ABNORMAL AND SUSTAINED INFLAMMATORY RESPONSE, WITH NEUTROPHILS BEING KEY EFFECTOR CELLS IN THE PATHOLOGICAL PROCESS. STUDIES HAVE DESCRIBED ABERRANT NEUTROPHIL FUNCTIONS ACROSS THESE CONDITIONS, AND SOME HAVE HIGHLIGHTED POTENTIAL MECHANISMS FOR ALTERED CELL BEHAVIOURS WHICH APPEAR SHARED ACROSS DISEASE STATES. IT HAS BEEN SUGGESTED THAT ALTERED FUNCTIONS MAY REPRESENT NEUTROPHIL "SENESCENCE". THIS REVIEW CONSIDERS HOW AND WHY NEUTROPHIL FUNCTIONS CHANGE AS THE CELL AGES, AND HOW AND WHY NEUTROPHIL FUNCTIONS CHANGE AS THE HOST AGES IN HEALTH AND DISEASE AND DISCUSSES WHETHER NEUTROPHIL FUNCTIONS COULD BE TARGETED TO IMPROVE HEALTH OUTCOMES IN OLDER ADULTS. 2018 17 3404 36 HOW EPIGENETICS IMPACTS ON HUMAN DISEASES. EPIGENETICS IS A RAPIDLY GROWING FIELD OF BIOLOGY THAT STUDIES THE CHANGES IN GENE EXPRESSION THAT ARE NOT DUE TO ALTERATIONS IN THE DNA SEQUENCE BUT RATHER THE CHEMICAL MODIFICATIONS OF DNA AND ITS ASSOCIATED PROTEINS. EPIGENETIC MECHANISMS CAN PROFOUNDLY INFLUENCE GENE EXPRESSION, CELL DIFFERENTIATION, TISSUE DEVELOPMENT, AND DISEASE SUSCEPTIBILITY. UNDERSTANDING EPIGENETIC CHANGES IS ESSENTIAL TO ELUCIDATE THE MECHANISMS UNDERLYING THE INCREASINGLY RECOGNIZED ROLE OF ENVIRONMENTAL AND LIFESTYLE FACTORS IN HEALTH AND DISEASE AND THE INTERGENERATIONAL TRANSMISSION OF PHENOTYPES. RECENT STUDIES SUGGEST EPIGENETICS MAY BE CRITICAL IN VARIOUS DISEASES, FROM CARDIOVASCULAR DISEASE AND CANCER TO NEURODEVELOPMENTAL AND NEURODEGENERATIVE DISORDERS. EPIGENETIC MODIFICATIONS ARE POTENTIALLY REVERSIBLE AND COULD PROVIDE NEW THERAPEUTIC AVENUES FOR TREATING THESE DISEASES USING EPIGENETIC MODULATORS. MOREOVER, EPIGENETICS PROVIDE INSIGHT INTO DISEASE PATHOGENESIS AND BIOMARKERS FOR DISEASE DIAGNOSIS AND RISK STRATIFICATION. NEVERTHELESS, EPIGENETIC INTERVENTIONS HAVE THE POTENTIAL FOR UNINTENDED CONSEQUENCES AND MAY POTENTIALLY LEAD TO INCREASED RISKS OF UNEXPECTED OUTCOMES, SUCH AS ADVERSE DRUG REACTIONS, DEVELOPMENTAL ABNORMALITIES, AND CANCER. THEREFORE, RIGOROUS STUDIES ARE ESSENTIAL TO MINIMIZE THE RISKS ASSOCIATED WITH EPIGENETIC THERAPIES AND TO DEVELOP SAFE AND EFFECTIVE INTERVENTIONS FOR IMPROVING HUMAN HEALTH. THIS ARTICLE PROVIDES A SYNTHETIC AND HISTORICAL VIEW OF THE ORIGIN OF EPIGENETICS AND SOME OF THE MOST RELEVANT ACHIEVEMENTS. 2023 18 6905 29 [THE ROLE OF EPIGENETIC REGULATIONS IN EARLY CHILDHOOD DISEASES]. WITH THE ACCEPTANCE OF "THE DEVELOPMENTAL ORIGINS OF HEALTH AND DISEASE" CONCEPT IN THE 1990S, IT BECAME CLEAR THAT EPIGENETIC INHERITANCE, WHICH DO NOT INVOLVE CHANGES IN THE DNA SEQUENCE HAS IMPORTANT ROLE IN THE PATHOGENESIS OF DISEASES. EPIGENETIC REGULATION SERVES THE ADAPTATION TO THE CHANGING ENVIRONMENT AND MAINTAINS THE REPRODUCTIVE FITNESS EVEN ON THE DRAWBACK OF INCREASED RISK OF DISEASES IN LATER LIFE. THE ROLE OF EPIGENETIC MECHANISMS IN CHRONIC NON-COMMUNICABLE DISEASES HAS BEEN WELL ESTABLISHED. RECENT STUDIES HAVE REVEALED THAT EPIGENETIC CHANGES HAVE ALSO CAUSAL ROLE IN CERTAIN PEDIATRIC DISEASES. THE REVIEW EVALUATES THE RECENT EPIGENETIC FINDINGS IN THE PATHOMECHANISM OF COMMON PEDIATRIC DISEASES. THE WIDE RANGE AND LONG-LASTING DURATION OF EPIGENETIC REGULATIONS GIVE IMPORTANCE TO THE SUBJECT. METHODS ARE ALREADY AVAILABLE TO EVALUATE A PART OF THE EPIGENETIC CHANGES IN THE CLINICAL PRACTICE, PRESENTLY AIMING PRIMARILY THE ESTIMATION OF THE DISEASE RISK OR DEFINITION OF DIAGNOSIS. FURTHERMORE, THERE ARE ALREADY AVAILABLE LIMITED MEANS TO INFLUENCE THE EPIGENETIC REGULATION. 2019 19 4419 36 MOLECULAR AND EPIGENETIC MARKERS AS PROMISING TOOLS TO QUANTIFY THE EFFECT OF OCCUPATIONAL EXPOSURES AND THE RISK OF DEVELOPING NON-COMMUNICABLE DISEASES. NON-COMMUNICABLE DISEASES (NCDS) ARE CHRONIC DISEASES THAT ARE BY FAR THE LEADING CAUSE OF DEATH IN THE WORLD. MANY OCCUPATIONAL HAZARDS, TOGETHER WITH SOCIAL, ECONOMIC AND DEMOGRAPHIC FACTORS, HAVE BEEN ASSOCIATED TO NCDS DEVELOPMENT. GENETIC SUSCEPTIBILITY OR ENVIRONMENTAL EXPOSURES ALONE ARE NOT USUALLY SUFFICIENT TO EXPLAIN THE PATHOGENESIS OF NCDS, BUT CAN BE INTEGRATED IN A MORE COMPLEX SCENARIO THAT CAN RESULT IN PATHOLOGICAL PHENOTYPES. EPIGENETICS IS A CRUCIAL COMPONENT OF THIS SCENARIO, AS ITS CHANGES ARE RELATED TO SPECIFIC EXPOSURES, THEREFORE POTENTIALLY ABLE TO DISPLAY THE EFFECTS OF ENVIRONMENT ON THE GENOME, FILLING THE GAP BETWEEN GENETIC ASSET AND ENVIRONMENT IN EXPLAINING DISEASE DEVELOPMENT. TO DATE, THE MOST PROMISING BIOMARKERS HAVE BEEN ASSESSED IN OCCUPATIONAL COHORTS AS WELL AS IN CASE/CONTROL STUDIES AND INCLUDE DNA METHYLATION, HISTONE MODIFICATIONS, MICRORNA EXPRESSION, EXTRACELLULAR VESICLES, TELOMERE LENGTH, AND MITOCHONDRIAL ALTERATIONS. 2019 20 3848 27 IS EPIGENETICS AN IMPORTANT LINK BETWEEN EARLY LIFE EVENTS AND ADULT DISEASE? BACKGROUND: EPIGENETIC MECHANISMS PROVIDE ONE POTENTIAL EXPLANATION FOR HOW ENVIRONMENTAL INFLUENCES IN EARLY LIFE CAUSE LONG-TERM CHANGES IN CHRONIC DISEASE SUSCEPTIBILITY. WHEREAS EPIGENETIC DYSREGULATION IS INCREASINGLY IMPLICATED IN VARIOUS RARE DEVELOPMENTAL SYNDROMES AND CANCER, THE ROLE OF EPIGENETICS IN COMPLEX CHRONIC DISEASES, SUCH AS CARDIOVASCULAR DISEASE, TYPE 2 DIABETES AND OBESITY, REMAINS LARGELY UNCHARACTERIZED. EXTENSIVE WORK IN ANIMAL MODELS IS REQUIRED TO DEVELOP SPECIFIC HYPOTHESES THAT CAN BE PRACTICABLY TESTED IN HUMANS. ANIMAL MODELS: WE HAVE DEVELOPED A MOUSE MODEL SHOWING THAT METHYL DONOR SUPPLEMENTATION PREVENTS TRANSGENERATIONAL AMPLIFICATION OF OBESITY, SUGGESTING A ROLE FOR DNA METHYLATION IN THE DEVELOPMENTAL ESTABLISHMENT OF BODY WEIGHT REGULATION. CONCLUSIONS: COUPLING SUCH MODELS WITH RECENTLY DEVELOPED EPIGENOMIC TECHNOLOGIES SHOULD ULTIMATELY ENABLE US TO DETERMINE IF EPIGENETICS IS AN IMPORTANT LINK BETWEEN EARLY LIFE EVENTS AND ADULT DISEASE. 2009