1 6426 104 THE TRANSGENERATIONAL TRANSMISSION OF THE PATERNAL TYPE 2 DIABETES-INDUCED SUBFERTILITY PHENOTYPE. DIABETES IS A CHRONIC METABOLIC DISORDER CHARACTERIZED BY HYPERGLYCEMIA AND ASSOCIATED WITH MANY HEALTH COMPLICATIONS DUE TO THE LONG-TERM DAMAGE AND DYSFUNCTION OF VARIOUS ORGANS. A CONSEQUENTIAL COMPLICATION OF DIABETES IN MEN IS REPRODUCTIVE DYSFUNCTION, REDUCED FERTILITY, AND POOR REPRODUCTIVE OUTCOMES. HOWEVER, THE MOLECULAR MECHANISMS RESPONSIBLE FOR DIABETIC ENVIRONMENT-INDUCED SPERM DAMAGE AND OVERALL DECREASED REPRODUCTIVE OUTCOMES ARE NOT FULLY ESTABLISHED. WE EVALUATED THE EFFECTS OF TYPE 2 DIABETES EXPOSURE ON THE REPRODUCTIVE SYSTEM AND THE REPRODUCTIVE OUTCOMES OF MALES AND THEIR MALE OFFSPRING, USING A MOUSE MODEL. WE DEMONSTRATE THAT PATERNAL EXPOSURE TO TYPE 2 DIABETES MEDIATES INTERGENERATIONAL AND TRANSGENERATIONAL EFFECTS ON THE REPRODUCTIVE HEALTH OF THE OFFSPRING, ESPECIALLY ON SPERM QUALITY, AND ON METABOLIC CHARACTERISTICS. GIVEN THE TRANSGENERATIONAL IMPAIRMENT OF REPRODUCTIVE AND METABOLIC PARAMETERS THROUGH TWO GENERATIONS, THESE CHANGES LIKELY TAKE THE FORM OF INHERITED EPIGENETIC MARKS THROUGH THE GERMLINE. OUR RESULTS EMPHASIZE THE IMPORTANCE OF IMPROVING METABOLIC HEALTH NOT ONLY IN WOMEN OF REPRODUCTIVE AGE, BUT ALSO IN POTENTIAL FATHERS, IN ORDER TO REDUCE THE NEGATIVE IMPACTS OF DIABETES ON SUBSEQUENT GENERATIONS. 2021 2 4941 40 PATERNAL OBESITY, INTERVENTIONS, AND MECHANISTIC PATHWAYS TO IMPAIRED HEALTH IN OFFSPRING. BACKGROUND: THE GLOBAL RATES OF MALE OVERWEIGHT/OBESITY ARE RISING, APPROACHING 70% OF THE TOTAL ADULT POPULATION IN WESTERN NATIONS. OVERWEIGHT/OBESITY INCREASES THE RISK OF CHRONIC DISEASES; HOWEVER, THERE IS INCREASING AWARENESS THAT MALE OBESITY NEGATIVELY IMPACTS FERTILITY, SUBSEQUENT PREGNANCY, AND THE OFFSPRING HEALTH BURDEN. DEVELOPMENTAL PROGRAMMING IS WELL DEFINED IN MOTHERS; HOWEVER, IT IS BECOMING INCREASINGLY EVIDENT THAT DEVELOPMENTAL PROGRAMMING CAN BE PATERNALLY INITIATED AND MEDIATED THROUGH PATERNAL OBESITY. KEY MESSAGES: BOTH HUMAN AND RODENT MODELS HAVE ESTABLISHED THAT PATERNAL OBESITY IMPAIRS SEX HORMONES, BASIC SPERM FUNCTION, AND MOLECULAR COMPOSITION. THIS RESULTS IN PERTURBED EMBRYO DEVELOPMENT AND HEALTH AND AN INCREASED SUBSEQUENT OFFSPRING DISEASE BURDEN IN BOTH SEXES. THE REVERSIBILITY OF OBESITY-INDUCED PARENTAL PROGRAMMING HAS ONLY RECENTLY RECEIVED ATTENTION. PROMISING RESULTS IN ANIMAL MODELS UTILIZING DIET AND EXERCISE INTERVENTIONS HAVE SHOWN IMPROVEMENTS IN SPERM FUNCTION AND MOLECULAR COMPOSITION, RESULTING IN RESTORATIONS OF BOTH EMBRYO AND FETAL HEALTH AND SUBSEQUENT MALE OFFSPRING FERTILITY. THE DIRECT MODE FOR PATERNAL INHERITANCE IS LIKELY MEDIATED VIA SPERMATOZOA. WE PROPOSE TWO MAIN THEORIES FOR THE ORIGIN OF MALE OBESITY-INDUCED PATERNAL PROGRAMMING: (1) ACCUMULATION OF SPERM DNA DAMAGE RESULTING IN DE NOVO MUTATIONS IN THE EMBRYO AND (2) CHANGES IN SPERM EPIGENETIC MARKS (MICRORNA, METHYLATION, OR ACETYLATION) ALTERING THE ACCESS, TRANSCRIPTION, AND TRANSLATION OF PATERNALLY DERIVED GENES DURING EARLY EMBRYOGENESIS. CONCLUSIONS: PATERNAL OVERWEIGHT/OBESITY INDUCES PATERNAL PROGRAMMING OF OFFSPRING PHENOTYPES LIKELY MEDIATED THROUGH GENETIC AND EPIGENETIC CHANGES IN SPERMATOZOA. THESE PROGRAMMED CHANGES TO OFFSPRING HEALTH APPEAR TO BE PARTIALLY RESTORED VIA DIET/EXERCISE INTERVENTIONS IN OBESE FATHERS PRECONCEPTION, WHICH HAVE BEEN SHOWN TO IMPROVE ASPECTS OF SPERM DNA INTEGRITY. HOWEVER, THE MAJORITY OF DATA SURROUNDING PATERNAL OBESITY AND OFFSPRING PHENOTYPES HAVE COME FROM RODENT MODELS; THEREFORE, WE CONTEND THAT IT WILL BE INCREASINGLY IMPORTANT TO STUDY POPULATION-BASED DATA TO DETERMINE THE LIKELY MODE OF INHERITANCE IN HUMANS. 2014 3 1921 43 ENVIRONMENTAL EPIGENETIC INHERITANCE THROUGH GAMETES AND IMPLICATIONS FOR HUMAN REPRODUCTION. BACKGROUND: TRADITIONAL STUDIES FOCUSED ON DNA AS THE HERITABLE INFORMATION CARRIER THAT PASSES THE PHENOTYPE FROM PARENTS TO OFFSPRING. HOWEVER, INCREASING EVIDENCE SUGGESTS THAT INFORMATION, THAT IS INDEPENDENT OF THE DNA SEQUENCE, TERMED EPIGENETIC INFORMATION, CAN BE INHERITED BETWEEN GENERATIONS. RECENTLY, IN OUR LAB, WE FOUND THAT PREDIABETES IN FATHERS INCREASES THE SUSCEPTIBILITY TO DIABETES IN OFFSPRING THROUGH GAMETIC CYTOSINE METHYLATION CHANGES. PATERNAL PREDIABETES CHANGED OVERALL METHYLATION PATTERNS IN SPERM, AND A LARGE PORTION OF DIFFERENTIALLY METHYLATED LOCI CAN BE TRANSMITTED TO PANCREATIC ISLETS OF OFFSPRING UP TO THE SECOND GENERATION. IN THIS REVIEW, WE SURVEY THE EXTENSIVE EXAMPLES OF ENVIRONMENTALLY INDUCED EPIGENETIC INHERITANCE IN VARIOUS SPECIES, RANGING FROM CAENORHABDITIS ELEGANS TO HUMANS. WE FOCUS MAINLY ON ELUCIDATING THE MOLECULAR BASIS OF ENVIRONMENTAL EPIGENETIC INHERITANCE THROUGH GAMETES, WHICH IS AN EMERGING THEME AND HAS IMPORTANT IMPLICATIONS FOR EXPLAINING THE PREVALENCE OF OBESITY, TYPE 2 DIABETES AND OTHER CHRONIC NON-GENETIC DISEASES, WHICH IS ALSO IMPORTANT FOR UNDERSTANDING THE INFLUENCE OF ENVIRONMENTAL EXPOSURES ON REPRODUCTIVE AND OVERALL HEALTH IN OFFSPRING. METHODS: FOR THIS REVIEW, WE INCLUDED RELEVANT DATA AND INFORMATION OBTAINED THROUGH A PUBMED DATABASE SEARCH FOR ALL ENGLISH LANGUAGE ARTICLES PUBLISHED UP TO AUGUST 2014 WHICH INCLUDED THE TERM 'ENVIRONMENTAL EPIGENETIC INHERITANCE' AND 'TRANSGENERATIONAL EPIGENETIC INHERITANCE'. WE FOCUSED ON RESEARCH PAPERS USING ANIMAL MODELS INCLUDING DROSOPHILA, C. ELEGANS, MOUSE AND RAT. HUMAN DATA WERE ALSO INCLUDED. RESULTS: EVIDENCE FROM ANIMAL MODELS SUGGESTS THAT ENVIRONMENTAL EPIGENETIC INHERITANCE THROUGH GAMETES EXISTS IN VARIOUS SPECIES. EXTENSIVE MOLECULAR EVIDENCE SUGGESTS THAT EPIGENETIC INFORMATION CARRIERS INCLUDING DNA METHYLATION, NON-CODING RNAS AND CHROMATIN PROTEINS IN GAMETES PLAY IMPORTANT ROLES IN THE TRANSMISSION OF PHENOTYPES FROM PARENTS TO OFFSPRING. CONCLUSIONS: GIVEN THE LARGE NUMBER OF EXPERIMENTAL EVIDENCE FROM VARIOUS ORGANISMS, IT IS CLEAR THAT PARENTAL ENVIRONMENTAL ALTERATIONS CAN AFFECT THE PHENOTYPES OF OFFSPRING THROUGH GAMETIC EPIGENETIC ALTERATIONS. THIS MORE RECENT THINKING BASED ON NEW DATA MAY HAVE IMPLICATIONS IN EXPLAINING THE PREVALENCE OF OBESITY, TYPE 2 DIABETES AND OTHER CHRONIC NON-GENETIC DISEASES. THIS ALSO IMPLIES THAT, IN THE NEAR FUTURE, EPIGENETIC FACTORS WHICH ARE HERITABLE SHOULD BE REGARDED IMPORTANT IN DETERMINING THE RISK OF CERTAIN DISEASES. MOREOVER, IDENTIFICATION OF EPIGENETIC MARKERS IN GAMETES (POLAR BODY OR SPERM) MAY HOLD GREAT PROMISE FOR PREDICTING SUSCEPTIBILITY TO AND PREVENTING CERTAIN NON-GENETIC DISEASES IN OFFSPRING, AS WELL AS PROVIDING INDICATIONS ON PARENTAL ENVIRONMENTAL EXPOSURES. 2015 4 4942 35 PATERNAL OBESITY: HOW BAD IS IT FOR SPERM QUALITY AND PROGENY HEALTH? THERE IS SUBSTANTIAL EVIDENCE THAT PATERNAL OBESITY IS ASSOCIATED NOT ONLY WITH AN INCREASED INCIDENCE OF INFERTILITY, BUT ALSO WITH AN INCREASED RISK OF METABOLIC DISTURBANCE IN ADULT OFFSPRING. APPARENTLY, SEVERAL MECHANISMS MAY CONTRIBUTE TO THE SPERM QUALITY ALTERATIONS ASSOCIATED WITH PATERNAL OBESITY, SUCH AS PHYSIOLOGICAL/HORMONAL ALTERATIONS, OXIDATIVE STRESS, AND EPIGENETIC ALTERATIONS. ALONG THESE LINES, MODIFICATIONS OF HORMONAL PROFILES NAMELY REDUCED ANDROGEN LEVELS AND ELEVATED ESTROGEN LEVELS, WERE FOUND ASSOCIATED WITH LOWER SPERM CONCENTRATION AND SEMINAL VOLUME. ADDITIONALLY, OXIDATIVE STRESS IN TESTIS MAY INDUCE AN INCREASE OF THE PERCENTAGE OF SPERM WITH DNA FRAGMENTATION. THE LATTER, RELATE TO OTHER PECULIARITIES SUCH AS ALTERATION OF THE EMBRYONIC DEVELOPMENT, INCREASED RISK OF MISCARRIAGE, AND DEVELOPMENT OF CHRONIC MORBIDITY IN THE OFFSPRING, INCLUDING CHILDHOOD CANCERS. UNDOUBTEDLY, EPIGENETIC ALTERATIONS (IE, DNA METHYLATION, CHROMATIN MODIFICATIONS, AND SMALL RNA DEREGULATION) OF SPERM RELATED TO PATERNAL OBESITY AND THEIR CONSEQUENCES ON THE PROGENY ARE POORLY UNDERSTOOD DETERMINANTS OF PATERNAL OBESITY-INDUCED TRANSMISSION. IN THIS REVIEW, WE SUMMARIZE AND DISCUSS THE DATA AVAILABLE IN THE LITERATURE REGARDING THE BIOLOGICAL, PHYSIOLOGICAL, AND MOLECULAR CONSEQUENCES OF PATERNAL OBESITY ON MALE FERTILITY POTENTIAL AND ULTIMATELY PROGENY HEALTH. 2017 5 3632 29 INCORPORATING TRANSGENERATIONAL EPIGENETIC INHERITANCE INTO ECOLOGICAL RISK ASSESSMENT FRAMEWORKS. CHRONIC EXPOSURE TO ENVIRONMENTAL CONTAMINANTS CAN INDUCE HERITABLE "TRANSGENERATIONAL" MODIFICATIONS TO ORGANISMS, POTENTIALLY AFFECTING FUTURE ECOSYSTEM HEALTH AND FUNCTIONALITY. INCORPORATING TRANSGENERATIONAL EPIGENETIC HERITABILITY INTO RISK ASSESSMENT PROCEDURES HAS BEEN PREVIOUSLY SUGGESTED. HOWEVER, A CRITICAL REVIEW OF EXISTING LITERATURE YIELDED NUMEROUS STUDIES CLAIMING TRANSGENERATIONAL IMPACTS, WITH LITTLE COMPELLING EVIDENCE. THEREFORE, CONTAMINANT-INDUCED EPIGENETIC INHERITANCE MAY BE LESS COMMON THAN IS REPORTED IN THE LITERATURE. WE IDENTIFIED A NEED FOR MULTIGENERATION EPIGENETIC STUDIES THAT EXTEND BEYOND WHAT COULD BE DEEMED "DIRECT EXPOSURE" TO F1 AND F2 GAMETES AND ALSO INCLUDE SUBSEQUENT MULTIPLE NONEXPOSED GENERATIONS TO ADEQUATELY EVALUATE TRANSGENERATIONAL RECOVERY TIMES. ALSO, INCREASED EXPERIMENTAL REPLICATION IS REQUIRED TO ACCOUNT FOR THE HIGHLY VARIABLE NATURE OF EPIGENETIC RESPONSES AND APPARENT IRREPRODUCIBILITY OF CURRENT STUDIES. FURTHER, EPIGENETIC END POINTS NEED TO BE CORRELATED WITH OBSERVABLE DETRIMENTAL ORGANISM CHANGES BEFORE A NEED FOR RISK MANAGEMENT CAN BE PROPERLY DETERMINED. WE SUGGEST THAT EPIGENETIC-BASED CONTAMINANT STUDIES INCLUDE CONCENTRATIONS LOWER THAN CURRENT "EC(10-20)" OR "LOWEST OBSERVABLE EFFECT CONCENTRATIONS" FOR THE ORGANISM'S MOST SENSITIVE PHENOTYPIC END POINT, AS HIGHER CONCENTRATIONS ARE LIKELY ALREADY REGULATED. FINALLY, WE PROPOSE A REGULATORY FRAMEWORK AND OPTIMAL EXPERIMENTAL DESIGN THAT ENABLES TRANSGENERATIONAL EPIGENETIC EFFECTS TO BE ASSESSED AND INCORPORATED INTO CONVENTIONAL ECOTOXICOLOGICAL TESTING. 2017 6 3119 29 GESTATIONAL EXPOSURE TO PARTICULATE AIR POLLUTION EXACERBATES THE GROWTH PHENOTYPES INDUCED BY PRECONCEPTION PATERNAL ALCOHOL USE: A MULTIPLEX MODEL OF EXPOSURE. IT IS NOW CLEAR THAT PARENTAL HISTORIES OF DRUG USE, TOXICANT EXPOSURE, AND SOCIAL STRESS ALL HAVE A SIGNIFICANT INFLUENCE ON THE HEALTH AND DEVELOPMENT OF THE NEXT GENERATION. HOWEVER, THE ABILITY OF EPIGENETIC PARENTAL LIFE MEMORIES TO INTERACT WITH SUBSEQUENT GESTATIONAL EXPOSURES AND CUMULATIVELY MODIFY THE DEVELOPMENTAL TRAJECTORY OF THE OFFSPRING REMAINS AN UNEXPLORED PERSPECTIVE IN TOXICOLOGY. STUDIES FROM OUR LABORATORY HAVE IDENTIFIED MALE-SPECIFIC POSTNATAL GROWTH RESTRICTION IN A MOUSE MODEL OF CHRONIC, PRECONCEPTION PATERNAL ALCOHOL EXPOSURE. THE GOAL OF THE CURRENT STUDY WAS TO DETERMINE IF PATERNAL ALCOHOL USE, BEFORE CONCEPTION, COULD MODIFY THE SUSCEPTIBILITY OF THE OFFSPRING TO A COMPLETELY SEPARATE EXPOSURE ENCOUNTERED BY THE MOTHER DURING PREGNANCY. IN INDEPENDENT EXPERIMENTS, WE PREVIOUSLY IDENTIFIED ALTERED DEVELOPMENTAL PROGRAMMING AND INCREASED MARKERS OF SEVERE ASTHMA INDUCED BY GESTATIONAL EXPOSURE TO PARTICULATE AIR POLLUTION. IN THIS STUDY, MALE MICE WERE EXPOSED TO EITHER THE CONTROL OR ALCOHOL PRECONCEPTION TREATMENTS, THEN MATED TO NAIVE FEMALES, WHICH WE SUBSEQUENTLY EXPOSED TO AN ULTRAFINE MIXTURE OF PARTICULATE MATTER VIA INHALATION. INDIVIDUALLY, NEITHER PRECONCEPTION PATERNAL DRINKING NOR GESTATIONAL EXPOSURES TO PARTICULATE AIR POLLUTION IMPACTED THE POSTNATAL GROWTH OF FEMALE OFFSPRING. HOWEVER, WHEN BOTH EXPOSURES WERE COMBINED, FEMALES DISPLAYED A 30% REDUCTION IN WEIGHT GAIN. UNEXPECTEDLY, THIS EXPOSURE PARADIGM RESULTED IN A DRAMATIC POSTNATAL INCREASE IN LITTER LOSS DUE TO MATERNAL CANNIBALISM, WHICH PREVENTED ADDITIONAL MEASURES OF OFFSPRING HEALTH. THESE PRELIMINARY STUDIES PROVIDE EVIDENCE OF A COMPLEX INTERPLAY BETWEEN PRECONCEPTION LIFE HISTORY AND INTRAUTERINE ENVIRONMENTAL FACTORS IN THE CONTROL OF POSTNATAL GROWTH. 2020 7 4790 35 NUTRITIONAL ADVERSITY, SEX AND REPRODUCTION: 30 YEARS OF DOHAD AND WHAT HAVE WE LEARNED? IT IS WELL ESTABLISHED THAT EARLY LIFE ENVIRONMENTAL SIGNALS, INCLUDING NUTRITION, SET THE STAGE FOR LONG-TERM HEALTH AND DISEASE RISK - EFFECTS THAT SPAN MULTIPLE GENERATIONS. THIS RELATIONSHIP BEGINS EARLY, IN THE PERICONCEPTIONAL PERIOD AND EXTENDS INTO EMBRYONIC, FETAL AND EARLY INFANT PHASES OF LIFE. NOW KNOWN AS THE DEVELOPMENTAL ORIGINS OF HEALTH AND DISEASE (DOHAD), THIS CONCEPT DESCRIBES THE ADAPTATIONS THAT A DEVELOPING ORGANISM MAKES IN RESPONSE TO EARLY LIFE CUES, RESULTING IN ADJUSTMENTS IN HOMEOSTATIC SYSTEMS THAT MAY PROVE MALADAPTIVE IN POSTNATAL LIFE, LEADING TO AN INCREASED RISK OF CHRONIC DISEASE AND/OR THE INHERITANCE OF RISK FACTORS ACROSS GENERATIONS. REPRODUCTIVE MATURATION AND FUNCTION IS SIMILARLY INFLUENCED BY EARLY LIFE EVENTS. THIS SHOULD NOT BE SURPRISING, SINCE PRIMORDIAL GERM CELLS ARE ESTABLISHED EARLY IN LIFE AND THUS VULNERABLE TO EARLY LIFE ADVERSITY. A MULTITUDE OF 'MODIFYING' CUES INDUCING DEVELOPMENTAL ADAPTATIONS HAVE BEEN IDENTIFIED THAT RESULT IN CHANGES IN REPRODUCTIVE DEVELOPMENT AND IMPAIRMENTS IN REPRODUCTIVE FUNCTION. MANY TYPES OF NUTRITIONAL CHALLENGES INCLUDING CALORIC RESTRICTION, MACRONUTRIENT EXCESS AND MICRONUTRIENT INSUFFICIENCIES HAVE BEEN SHOWN TO INDUCE EARLY LIFE ADAPTATIONS THAT PRODUCE LONG-TERM REPRODUCTIVE DYSFUNCTION. MANY PATHWAYS HAVE BEEN SUGGESTED TO UNDERPIN THESE ASSOCIATIONS, INCLUDING EPIGENETIC REPROGRAMMING OF GERM CELLS. WHILE THE MECHANISMS STILL REMAIN TO BE FULLY INVESTIGATED, IT IS CLEAR THAT A LIFECOURSE APPROACH TO UNDERSTANDING LIFETIME REPRODUCTIVE FUNCTION IS NECESSARY. FURTHERMORE, INVESTIGATIONS OF THE IMPACTS OF EARLY LIFE ADVERSITY MUST BE EXTENDED TO INCLUDE THE PATERNAL ENVIRONMENT, ESPECIALLY IN EPIDEMIOLOGICAL AND CLINICAL STUDIES OF OFFSPRING REPRODUCTIVE FUNCTION. 2019 8 4496 32 MORE THAN GENES: THE ADVANCED FETAL PROGRAMMING HYPOTHESIS. MANY LINES OF DATA, INITIAL EPIDEMIOLOGIC STUDIES AS WELL AS SUBSEQUENT EXTENSIVE EXPERIMENTAL STUDIES, INDICATE THAT EARLY-LIFE EVENTS PLAY A POWERFUL ROLE IN INFLUENCING LATER SUCEPTIBILITY TO CERTAIN CHRONIC DISEASES. SUCH EVENTS MIGHT BE OVER- OR UNDERNUTRITION, EXPOSURE TO ENVIRONMENTAL TOXINS, BUT ALSO CHANGES IN HORMONES, IN PARTICULAR STRESS HORMONES. TYPICALLY, THOSE EVENTS ARE TRIGGERED BY THE ENVIRONMENTAL CHALLENGES OF THE MOTHER. HOWEVER, RECENT STUDIES HAVE SHOWN THAT PATERNAL ENVIRONMENTAL OR NUTRITIONAL FACTORS AFFECT THE PHENOTYPE OF THE OFFSPRING AS WELL. THE MATERNAL AND PATERNAL ENVIRONMENTAL FACTORS ACT ON THE PHENOTYPE OF THE OFFSPRING VIA EPIGENETIC MODIFICATION OF ITS GENOME. THE ADVANCED FETAL PROGRAMMING HYPOTHESIS PROPOSES AN ADDITIONAL NON-ENVIRONMENTALLY DRIVEN MECHANISM: MATERNAL AND ALSO PATERNAL GENES MAY INFLUENCE THE MATURATING SPERM, THE OOCYTE, AND LATER THE EMBRYO/FETUS, LEADING TO THEIR EPIGENETIC ALTERATION. THUS, THE OBSERVED PHENOTYPE OF THE OFFSPRING MAY BE ALTERED BY MATERNAL/PATERNAL GENES INDEPENDENT OF THE FETAL GENOME. MEANWHILE, SEVERAL INDEPENDENT ASSOCIATION STUDIES IN HUMANS DEALING WITH METABOLIC AND NEUROLOGICAL TRAITS ALSO SUGGEST THAT MATERNAL GENES MIGHT AFFECT THE OFFSPRING PHENOTYPE INDEPENDENT OF THE TRANSMISSION OF THAT PARTICULAR GENE TO THE OFFSPRING. CONSIDERING THE IMPLICATIONS OF THIS HYPOTHESIS, SOME CONCLUSIONS DRAWN FROM TRANSGENIC OR KNOCKOUT ANIMAL MODELS AND BASED ON THE CAUSALITY BETWEEN A GENETIC ALTERATION AND A PHENOTYPE, NEED TO BE CHALLENGED. POSSIBLE IMPLICATIONS FOR THE DEVELOPMENT, DIAGNOSTIC AND THERAPY OF HUMAN GENETIC DISEASES HAVE TO BE INVESTIGATED. 2014 9 1153 32 CONSEQUENCES OF PATERNAL NUTRITION ON OFFSPRING HEALTH AND DISEASE. IT IS WELL ESTABLISHED THAT THE MATERNAL DIET DURING THE PERICONCEPTIONAL PERIOD AFFECTS THE PROGENY'S HEALTH. A GROWING BODY OF EVIDENCE SUGGESTS THAT THE PATERNAL DIET ALSO INFLUENCES DISEASE ONSET IN OFFSPRING. FOR MANY YEARS, SPERM WAS CONSIDERED ONLY TO CONTRIBUTE HALF OF THE PROGENY'S GENOME. IT NOW APPEARS THAT IT ALSO PLAYS A CRUCIAL ROLE IN HEALTH AND DISEASE IN OFFSPRING'S ADULT LIFE. THE NUTRITIONAL STATUS AND ENVIRONMENTAL EXPOSURE OF FATHERS DURING THEIR CHILDHOOD AND/OR THE PERICONCEPTIONAL PERIOD HAVE SIGNIFICANT TRANSGENERATIONAL CONSEQUENCES. THIS REVIEW AIMS TO DESCRIBE THE EFFECTS OF VARIOUS HUMAN AND RODENT PATERNAL FEEDING PATTERNS ON PROGENY'S METABOLISM AND HEALTH, INCLUDING FASTING OR INTERMITTENT FASTING, LOW-PROTEIN AND FOLIC ACID DEFICIENT FOOD, AND OVERNUTRITION IN HIGH-FAT AND HIGH-SUGAR DIETS. THE IMPACT ON PREGNANCY OUTCOME, METABOLIC PATHWAYS, AND CHRONIC DISEASE ONSET WILL BE DESCRIBED. THE BIOLOGICAL AND EPIGENETIC MECHANISMS UNDERLYING THE TRANSMISSION FROM FATHERS TO THEIR PROGENY WILL BE DISCUSSED. ALL THESE DATA PROVIDE EVIDENCE OF THE IMPACT OF PATERNAL NUTRITION ON PROGENY HEALTH WHICH COULD LEAD TO PREVENTIVE DIET RECOMMENDATIONS FOR FUTURE FATHERS. 2021 10 5202 27 PRENATAL ORIGINS OF ADULT DISEASE. PURPOSE OF REVIEW: HUMAN EPIDEMIOLOGICAL AND ANIMAL STUDIES SHOW THAT MANY CHRONIC ADULT CONDITIONS HAVE THEIR ANTECEDENTS IN COMPROMISED FETAL AND EARLY POSTNATAL DEVELOPMENT. DEVELOPMENTAL PROGRAMMING IS DEFINED AS THE RESPONSE BY THE DEVELOPING MAMMALIAN ORGANISM TO A SPECIFIC CHALLENGE DURING A CRITICAL TIME WINDOW THAT ALTERS THE TRAJECTORY OF DEVELOPMENT WITH RESULTING PERSISTENT EFFECTS ON PHENOTYPE. MAMMALS PASS MORE BIOLOGICAL MILESTONES BEFORE BIRTH THAN ANY OTHER TIME IN THEIR LIVES. EACH INDIVIDUAL'S PHENOTYPE IS INFLUENCED BY THE DEVELOPMENTAL ENVIRONMENT AS MUCH AS THEIR GENES. A BETTER UNDERSTANDING IS REQUIRED OF GENE-ENVIRONMENT INTERACTIONS LEADING TO ADULT DISEASE. RECENT FINDINGS: DURING DEVELOPMENT, THERE ARE CRITICAL PERIODS OF VULNERABILITY TO SUBOPTIMAL CONDITIONS WHEN PROGRAMMING MAY PERMANENTLY MODIFY DISEASE SUSCEPTIBILITY. PROGRAMMING INVOLVES STRUCTURAL CHANGES IN IMPORTANT ORGANS; ALTERED CELL NUMBER, IMBALANCE IN DISTRIBUTION OF DIFFERENT CELL TYPES WITHIN THE ORGAN, AND ALTERED BLOOD SUPPLY OR RECEPTOR NUMBERS. COMPENSATORY EFFORTS BY THE FETUS MAY CARRY A PRICE. EFFECTS OF PROGRAMMING MAY PASS ACROSS GENERATIONS BY MECHANISMS THAT DO NOT NECESSARILY INVOLVE STRUCTURAL GENE CHANGES. PROGRAMMING OFTEN HAS DIFFERENT EFFECTS IN MALES AND FEMALES. SUMMARY: DEVELOPMENTAL PROGRAMMING SHOWS THAT EPIGENETIC FACTORS PLAY MAJOR ROLES IN DEVELOPMENT OF PHENOTYPE AND PREDISPOSITION TO DISEASE IN LATER LIFE. 2008 11 4863 31 ORIGINS OF LIFETIME HEALTH AROUND THE TIME OF CONCEPTION: CAUSES AND CONSEQUENCES. PARENTAL ENVIRONMENTAL FACTORS, INCLUDING DIET, BODY COMPOSITION, METABOLISM, AND STRESS, AFFECT THE HEALTH AND CHRONIC DISEASE RISK OF PEOPLE THROUGHOUT THEIR LIVES, AS CAPTURED IN THE DEVELOPMENTAL ORIGINS OF HEALTH AND DISEASE CONCEPT. RESEARCH ACROSS THE EPIDEMIOLOGICAL, CLINICAL, AND BASIC SCIENCE FIELDS HAS IDENTIFIED THE PERIOD AROUND CONCEPTION AS BEING CRUCIAL FOR THE PROCESSES MEDIATING PARENTAL INFLUENCES ON THE HEALTH OF THE NEXT GENERATION. DURING THIS TIME, FROM THE MATURATION OF GAMETES THROUGH TO EARLY EMBRYONIC DEVELOPMENT, PARENTAL LIFESTYLE CAN ADVERSELY INFLUENCE LONG-TERM RISKS OF OFFSPRING CARDIOVASCULAR, METABOLIC, IMMUNE, AND NEUROLOGICAL MORBIDITIES, OFTEN TERMED DEVELOPMENTAL PROGRAMMING. WE REVIEW PERICONCEPTIONAL INDUCTION OF DISEASE RISK FROM FOUR BROAD EXPOSURES: MATERNAL OVERNUTRITION AND OBESITY; MATERNAL UNDERNUTRITION; RELATED PATERNAL FACTORS; AND THE USE OF ASSISTED REPRODUCTIVE TREATMENT. STUDIES IN BOTH HUMANS AND ANIMAL MODELS HAVE DEMONSTRATED THE UNDERLYING BIOLOGICAL MECHANISMS, INCLUDING EPIGENETIC, CELLULAR, PHYSIOLOGICAL, AND METABOLIC PROCESSES. WE ALSO PRESENT A META-ANALYSIS OF MOUSE PATERNAL AND MATERNAL PROTEIN UNDERNUTRITION THAT SUGGESTS DISTINCT PARENTAL PERICONCEPTIONAL CONTRIBUTIONS TO POSTNATAL OUTCOMES. WE PROPOSE THAT THE EVIDENCE FOR PERICONCEPTIONAL EFFECTS ON LIFETIME HEALTH IS NOW SO COMPELLING THAT IT CALLS FOR NEW GUIDANCE ON PARENTAL PREPARATION FOR PREGNANCY, BEGINNING BEFORE CONCEPTION, TO PROTECT THE HEALTH OF OFFSPRING. 2018 12 2137 35 EPIGENETIC INHERITANCE AND EVOLUTION: A PATERNAL PERSPECTIVE ON DIETARY INFLUENCES. THE EARLIEST INDICATIONS FOR PATERNALLY INDUCED TRANSGENERATIONAL EFFECTS FROM THE ENVIRONMENT TO FUTURE GENERATIONS WERE BASED ON A SMALL NUMBER OF LONG-TERM EPIDEMIOLOGICAL STUDIES AND SOME EMPIRICAL OBSERVATIONS. ONLY RECENTLY HAVE EXPERIMENTAL ANIMAL MODELS AND A FEW ANALYSES ON HUMAN DATA EXPLORED THE TRANSGENERATIONAL NATURE OF PHENOTYPIC CHANGES OBSERVED IN OFFSPRING. CHANGES INCLUDE MULTIPLE METABOLIC DISORDERS, CANCER AND OTHER CHRONIC DISEASES. THESE PHENOTYPES CANNOT ALWAYS BE EXPLAINED BY MENDELIAN INHERITANCE, DNA MUTATIONS OR GENETIC DAMAGE. HENCE, A NEW COMPELLING THEORY ON EPIGENETIC INHERITANCE IS GAINING INTEREST, PROVIDING NEW CONCEPTS THAT EXTEND DARWIN'S EVOLUTIONARY THEORY. EPIGENETIC ALTERATIONS OR "EPIMUTATIONS" ARE BEING CONSIDERED TO EXPLAIN TRANSGENERATIONAL INHERITANCE OF PARENTALLY ACQUIRED TRAITS. THE RESPONSIBLE MECHANISMS FOR THESE EPIMUTATIONS INCLUDE DNA METHYLATION, HISTONE MODIFICATION, AND RNA-MEDIATED EFFECTS. THIS REVIEW EXPLORES THE LITERATURE ON A NUMBER OF TIME-DEPENDENT ENVIRONMENTALLY INDUCED EPIGENETIC ALTERATIONS, SPECIFICALLY THOSE FROM DIETARY EXPOSURES. WE SUGGEST A ROLE FOR THE MALE GERM LINE AS ONE OF NATURE'S TOOLS TO CAPTURE MESSAGES FROM OUR CONTINUOUSLY CHANGING ENVIRONMENT AND TO TRANSFER THIS INFORMATION TO SUBSEQUENT GENERATIONS. FURTHER, WE OPEN THE DISCUSSION THAT THE PATERNALLY INHERITED EPIGENETIC INFORMATION MAY CONTRIBUTE TO EVOLUTIONARY ADAPTATION. 2015 13 6554 28 TRANSGENERATIONAL EFFECTS OF EARLY ENVIRONMENTAL INSULTS ON AGING AND DISEASE INCIDENCE. ADVERSE EARLY LIFE EXPERIENCES ARE MAJOR INFLUENCES ON DEVELOPMENTAL TRAJECTORIES WITH POTENTIALLY LIFE-LONG CONSEQUENCES. PRENATAL OR EARLY POSTNATAL EXPOSURE TO STRESS, UNDERNUTRITION OR ENVIRONMENTAL TOXICANTS MAY REPROGRAM BRAIN DEVELOPMENT AND INCREASE RISK OF BEHAVIOURAL AND NEUROLOGICAL DISORDERS LATER IN LIFE. NOT ONLY EXPERIENCE WITHIN A SINGLE LIFETIME, BUT ALSO ANCESTRAL EXPERIENCE AFFECTS HEALTH TRAJECTORIES AND CHANCES OF SUCCESSFUL AGING. THE CENTRAL MECHANISM IN TRANSGENERATIONAL PROGRAMMING OF A DISEASE MAY BE THE FORMATION OF EPIGENETIC MEMORY. THIS REVIEW EXPLORES TRANSGENERATIONAL EFFECTS OF EARLY ADVERSE EXPERIENCE ON HEALTH AND DISEASE INCIDENCE IN OLDER AGE. FIRST, WE ADDRESS MECHANISMS OF DEVELOPMENTAL AND TRANSGENERATIONAL PROGRAMMING OF DISEASE AND INHERITANCE. SECOND, WE DISCUSS EXPERIMENTAL AND CLINICAL FINDINGS LINKING EARLY ENVIRONMENTAL DETERMINANTS TO ADVERSE AGING TRAJECTORIES IN ASSOCIATION WITH POSSIBLE PARENTAL CONTRIBUTIONS AND SEX-SPECIFIC EFFECTS. THIRD, WE OUTLINE THE MAIN MECHANISMS OF AGE-RELATED FUNCTIONAL DECLINE AND SUGGEST POTENTIAL INTERVENTIONS TO REVERSE NEGATIVE EFFECTS OF TRANSGENERATIONAL PROGRAMMING. THUS, STRATEGIES THAT SUPPORT HEALTHY DEVELOPMENT AND SUCCESSFUL AGING SHOULD TAKE INTO ACCOUNT THE POTENTIAL INFLUENCES OF TRANSGENERATIONAL INHERITANCE. 2020 14 6234 35 THE LONG-TERM EFFECTS OF PRENATAL DEVELOPMENT ON GROWTH AND METABOLISM. PEOPLE WHO WERE SMALL AT BIRTH AND HAD POOR INFANT GROWTH HAVE AN INCREASED RISK OF ADULT CARDIOVASCULAR DISEASE, OSTEOPOROSIS, AND TYPE 2 DIABETES, PARTICULARLY IF THEIR RESTRICTED EARLY GROWTH WAS FOLLOWED BY INCREASED CHILDHOOD WEIGHT GAIN. THESE RELATIONS EXTEND ACROSS THE NORMAL RANGE OF BIRTH SIZE IN A GRADED MANNER, SO REDUCED SIZE IS NOT A PREREQUISITE. IN ADDITION, LARGER BIRTH SIZE IS ASSOCIATED WITH RISKS OF OBESITY AND TYPE 2 DIABETES. THE ASSOCIATIONS APPEAR TO REFLECT DEVELOPMENTAL PLASTIC RESPONSES MADE BY THE FETUS AND INFANT BASED ON CUES ABOUT THE ENVIRONMENT, INFLUENCED BY MATERNAL CHARACTERISTICS INCLUDING DIET, BODY COMPOSITION, STRESS, AND EXERCISE LEVELS. THESE RESPONSES INVOLVE EPIGENETIC PROCESSES THAT MODIFY THE OFFSPRING'S PHENOTYPE. VULNERABILITY TO ILL HEALTH RESULTS IF THE ENVIRONMENT IN INFANCY, CHILDHOOD, AND LATER LIFE IS MISMATCHED TO THE PHENOTYPE INDUCED IN DEVELOPMENT, INFORMED BY THE DEVELOPMENTAL CUES. THIS MISMATCH MAY ARISE THROUGH UNBALANCED DIET OR BODY COMPOSITION OF THE MOTHER OR A CHANGE IN LIFESTYLE FACTORS BETWEEN GENERATIONS. THESE INSIGHTS OFFER NEW POSSIBILITIES FOR THE EARLY DIAGNOSIS AND PREVENTION OF CHRONIC DISEASE. 2011 15 5167 31 PRECONCEPTION PATERNAL MENTAL DISORDERS AND CHILD HEALTH: MECHANISMS AND INTERVENTIONS. MENTAL ILLNESS IS A SIGNIFICANT GLOBAL HEALTH ISSUE WITH A STEADY PREVALENCE. HIGH HERITABILITY IS SUSPECTED, BUT GENOME-WIDE ASSOCIATION STUDIES ONLY IDENTIFIED A SMALL NUMBER OF RISK GENES ASSOCIATED WITH MENTAL DISORDERS. THIS 'MISSING INHERITANCE' CAN BE PARTIALLY EXPLAINED BY EPIGENETIC HEREDITY. EVIDENCE FROM NUMEROUS ANIMAL MODELS AND HUMAN STUDIES SUPPORTS THE POSSIBILITY THAT PRECONCEPTION PATERNAL MENTAL HEALTH INFLUENCES THEIR OFFSPRING'S MENTAL HEALTH VIA NONGENETIC MEANS. HERE, WE REVIEW TWO POTENTIAL PATHWAYS, INCLUDING SPERM EPIGENETICS AND SEMINAL PLASMA COMPONENTS. THE CURRENT REVIEW HIGHLIGHTS THE ROLE OF SPERM EPIGENETICS AND EXPLORES EPIGENETIC MESSAGE ORIGINATION AND SUSCEPTIBILITY TO CHRONIC STRESS. MEANWHILE, POSSIBLE SPATIOTEMPORAL WINDOWS AND EVENTS THAT INDUCE SEXUALLY DIMORPHIC MODES AND EFFECTS OF PATERNAL STRESS TRANSMISSION ARE INFERRED IN THIS REVIEW. ADDITIONALLY, WE DISCUSS EMERGING INTERVENTIONS THAT COULD POTENTIALLY BLOCK THE INTERGENERATIONAL TRANSMISSION OF PATERNAL PSYCHIATRIC DISORDERS AND REDUCE THE INCIDENCE OF MENTAL ILLNESS. UNDERSTANDING THE UNDERLYING MECHANISMS BY WHICH PRECONCEPTION PATERNAL STRESS IMPACTS OFFSPRING HEALTH IS CRITICAL FOR IDENTIFYING STRATEGIES SUPPORTING HEALTHY DEVELOPMENT AND SUCCESSFULLY CONTROLLING THE PREVALENCE OF MENTAL ILLNESS. 2023 16 5578 32 ROLE OF MIRNA IN THE TRANSMISSION OF METABOLIC DISEASES ASSOCIATED WITH PATERNAL DIET-INDUCED OBESITY. THE CONCEPT OF DEVELOPMENTAL ORIGINS OF HEALTH AND DISEASES (DOHAD) RECOGNIZES THAT AN UNFAVORABLE MATERNAL ENVIRONMENT ALTERS THE DEVELOPMENTAL TRAJECTORY OF THE FETUS AND CAN LEAD TO LONG-TERM RISK OF DEVELOPING CHRONIC NONCOMMUNICABLE DISEASES. MORE RECENTLY, THE CONCEPT OF A PATERNAL TRANSMISSION [PATERNAL ORIGINS OF HEALTH AND DISEASES (POHAD)] HAS EMERGED STRESSING THE IMPACT OF PATERNAL OVERWEIGHT OR OBESITY ON OFFSPRING'S HEALTH AND DEVELOPMENT. WHILE VERY FEW EXAMPLES OF PATERNAL EPIGENETIC INHERITANCE OF METABOLIC DISORDERS HAVE BEEN EVIDENCED IN HUMAN, MANY EXPERIMENTAL MOUSE MODELS BASED ON HIGH-FAT DIET (HFD)-INDUCED PATERNAL OBESITY HAVE BEEN DEVELOPED TO BREAKDOWN MOLECULAR MECHANISMS INVOLVED IN THE PROCESS. BESIDES DNA METHYLATION AND CHROMATIN STRUCTURE, SPERM SHORT NONCODING RNAS HAVE BEEN CONSIDERED AS THE MAIN EPIGENETIC VECTOR OF INHERITANCE OF PATERNALLY ENVIRONMENTALLY INDUCED CHANGES. AMONG THEM, SPERM MIRNAS ARE ONE PARTICULAR SUBSPECIES SENSITIVE TO ENVIRONMENTAL CHANGES AND OBESITY CAN MODIFY THE SPERM MIRNA PROFILE. ONCE DELIVERED INTO THE ZYGOTE, THESE MOLECULES MIGHT INDUCE EPIGENETIC MODIFICATIONS IN THE EMBRYO, THEREBY LEADING TO CONSEQUENCES FOR FETUS DEVELOPMENT AND OFFSPRING PHYSICAL AND METABOLIC HEALTH LATER ON IN LIFE. FURTHERMORE, SOME DATA ALSO SUGGEST THAT METABOLIC PATHOLOGIES MAY BE INTERGENERATIONALLY OR TRANSGENERATIONALLY TRANSMITTED. 2019 17 260 27 ADVANCES IN RESEARCH INTO GAMETE AND EMBRYO-FETAL ORIGINS OF ADULT DISEASES. THE FETAL AND INFANT ORIGINS OF ADULT DISEASE HYPOTHESIS PROPOSED THAT THE ROOTS OF ADULT CHRONIC DISEASE LIE IN THE EFFECTS OF ADVERSE ENVIRONMENTS IN FETAL LIFE AND EARLY INFANCY. IN ADDITION TO THE FETAL PERIOD, FERTILIZATION AND EARLY EMBRYONIC STAGES, THE CRITICAL TIME WINDOWS OF EPIGENETIC REPROGRAMMING, RAPID CELL DIFFERENTIATION AND ORGANOGENESIS, ARE THE MOST SENSITIVE STAGES TO ENVIRONMENTAL DISTURBANCES. COMPARED WITH EMBRYO AND FETAL DEVELOPMENT, GAMETOGENESIS AND MATURATION TAKE DECADES AND ARE MORE VULNERABLE TO POTENTIAL DAMAGE FOR A LONGER EXPOSURE PERIOD. THEREFORE, WE SHOULD SHIFT THE FOCUS OF ADULT DISEASE OCCURRENCE AND PATHOGENESIS FURTHER BACK TO GAMETOGENESIS AND EMBRYONIC DEVELOPMENT EVENTS, WHICH MAY RESULT IN INTERGENERATIONAL, EVEN TRANSGENERATIONAL, EPIGENETIC RE-PROGRAMMING WITH TRANSMISSION OF ADVERSE TRAITS AND CHARACTERISTICS TO OFFSPRING. HERE, WE FOCUS ON THE RESEARCH PROGRESS RELATING TO DISEASES THAT ORIGINATED FROM EVENTS IN THE GAMETES AND EARLY EMBRYOS AND THE POTENTIAL EPIGENETIC MECHANISMS INVOLVED. 2019 18 4717 28 NON-GENOMIC TRANSGENERATIONAL INHERITANCE OF DISEASE RISK. THAT THERE IS A HERITABLE OR FAMILIAL COMPONENT OF SUSCEPTIBILITY TO CHRONIC NON-COMMUNICABLE DISEASES SUCH AS TYPE 2 DIABETES, OBESITY AND CARDIOVASCULAR DISEASE IS WELL ESTABLISHED, BUT THERE IS INCREASING EVIDENCE THAT SOME ELEMENTS OF SUCH HERITABILITY ARE TRANSMITTED NON-GENOMICALLY AND THAT THE PROCESSES WHEREBY ENVIRONMENTAL INFLUENCES ACT DURING EARLY DEVELOPMENT TO SHAPE DISEASE RISK IN LATER LIFE CAN HAVE EFFECTS BEYOND A SINGLE GENERATION. SUCH HERITABILITY MAY OPERATE THROUGH EPIGENETIC MECHANISMS INVOLVING REGULATION OF EITHER IMPRINTED OR NON-IMPRINTED GENES BUT ALSO THROUGH BROADER MECHANISMS RELATED TO PARENTAL PHYSIOLOGY OR BEHAVIOUR. WE REVIEW EVIDENCE AND POTENTIAL MECHANISMS FOR NON-GENOMIC TRANSGENERATIONAL INHERITANCE OF 'LIFESTYLE' DISEASE AND PROPOSE THAT THE 'DEVELOPMENTAL ORIGINS OF DISEASE' PHENOMENON IS A MALADAPTIVE CONSEQUENCE OF AN ANCESTRAL MECHANISM OF DEVELOPMENTAL PLASTICITY THAT MAY HAVE HAD ADAPTIVE VALUE IN THE EVOLUTION OF GENERALIST SPECIES SUCH AS HOMO SAPIENS. 2007 19 3771 35 INTER- AND TRANSGENERATIONAL EPIGENETIC INHERITANCE: EVIDENCE IN ASTHMA AND COPD? EVIDENCE IS NOW EMERGING THAT EARLY LIFE ENVIRONMENT CAN HAVE LIFELONG EFFECTS ON METABOLIC, CARDIOVASCULAR, AND PULMONARY FUNCTION IN OFFSPRING, A CONCEPT ALSO KNOWN AS FETAL OR DEVELOPMENTAL PROGRAMMING. IN MAMMALS, DEVELOPMENTAL PROGRAMMING IS THOUGHT TO OCCUR MAINLY VIA EPIGENETIC MECHANISMS, WHICH INCLUDE DNA METHYLATION, HISTONE MODIFICATIONS, AND EXPRESSION OF NON-CODING RNAS. THE EFFECTS OF DEVELOPMENTAL PROGRAMMING CAN BE INDUCED BY THE INTRAUTERINE ENVIRONMENT, LEADING TO INTERGENERATIONAL EPIGENETIC EFFECTS FROM ONE GENERATION TO THE NEXT. TRANSGENERATIONAL EPIGENETIC INHERITANCE MAY BE CONSIDERED WHEN DEVELOPMENTAL PROGRAMMING IS TRANSMITTED ACROSS GENERATIONS THAT WERE NOT EXPOSED TO THE INITIAL ENVIRONMENT WHICH TRIGGERED THE CHANGE. SO FAR, INTER- AND TRANSGENERATIONAL PROGRAMMING HAS BEEN MAINLY DESCRIBED FOR CARDIOVASCULAR AND METABOLIC DISEASE RISK. IN THIS REVIEW, WE DISCUSS AVAILABLE EVIDENCE THAT EPIGENETIC INHERITANCE ALSO OCCURS IN RESPIRATORY DISEASES, USING ASTHMA AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) AS EXAMPLES. WHILE MULTIPLE EPIDEMIOLOGICAL AS WELL AS ANIMAL STUDIES DEMONSTRATE EFFECTS OF 'TOXIC' INTRAUTERINE EXPOSURE ON VARIOUS ASTHMA-RELATED PHENOTYPES IN THE OFFSPRING, ONLY FEW STUDIES LINK EPIGENETIC MARKS TO THE OBSERVED PHENOTYPES. AS EPIGENETIC MARKS MAY DISTINGUISH INDIVIDUALS MOST AT RISK OF LATER DISEASE AT EARLY AGE, IT WILL ENABLE EARLY INTERVENTION STRATEGIES TO REDUCE SUCH RISKS. TO ACHIEVE THIS GOAL FURTHER, WELL DESIGNED EXPERIMENTAL AND HUMAN STUDIES ARE NEEDED. 2015 20 1371 27 DEVELOPMENTAL ORIGINS OF HEALTH AND DISEASE: NEW INSIGHTS. EPIDEMIOLOGICAL AND ANIMAL STUDIES SHOW THAT SMALL CHANGES IN THE DEVELOPMENTAL ENVIRONMENT CAN INDUCE PHENOTYPIC CHANGES AFFECTING AN INDIVIDUAL'S RESPONSES TO THEIR LATER ENVIRONMENT. THESE MAY ALTER THE RISK OF CHRONIC DISEASE SUCH AS METABOLIC SYNDROME OR CARDIOVASCULAR DISEASE. RECENT RESEARCH SHOWS THAT ANIMALS EXPOSED TO SUCH A MISMATCH BETWEEN PRENATAL AND POSTNATAL ENVIRONMENT DEVELOP OBESITY, REDUCED ACTIVITY, LEPTIN AND INSULIN RESISTANCE, ELEVATED BLOOD PRESSURE AND VASCULAR ENDOTHELIAL DYSFUNCTION. EPIGENETIC PROCESSES ARE INVOLVED IN SUCH EFFECTS, TARGETED TO PROMOTER REGIONS OF SPECIFIC GENES IN SPECIFIC TISSUES. SUCH FINE CONTROL OF GENE EXPRESSION SUGGESTS THAT THE MECHANISMS HAVE BEEN RETAINED THROUGH EVOLUTION THROUGH THEIR ADAPTIVE ADVANTAGE, RATHER THAN REPRESENTING EXTREME EFFECTS OF DEVELOPMENTAL DISRUPTION AKIN TO TERATOGENESIS. THERE MAY BE ADAPTIVE ADVANTAGE IN A DEVELOPMENTAL CUE INDUCING A PHENOTYPIC CHANGE IN GENERATIONS BEYOND THE IMMEDIATE PREGNANCY, AND A RANGE OF DATA THAT SUPPORT THIS CONCEPT. IN ANIMALS, EPIGENETIC EFFECTS SUCH AS DNA METHYLATION CAN BE PASSED TO SUCCESSIVE GENERATIONS. ENVIRONMENTAL TOXINS, INCLUDING ENDOCRINE DISRUPTORS, MAY INDUCE GREATER RISK OF CHRONIC DISEASE, EVEN AT LOW EXPOSURE LEVELS, IF THEY AFFECT SUCH NORMAL DEVELOPMENTAL EPIGENETIC PROCESSES. APPROPRIATE INTERVENTIONS MAY HAVE LONG-TERM MULTIGENERATIONAL EFFECTS TO REDUCE THE RISK OF CHRONIC DISEASE. 2008