1 247 119 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 2 120 41 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 3 6065 37 THE DEVELOPMENTAL ORIGINS OF CHRONIC PHYSICAL AGGRESSION: BIOLOGICAL PATHWAYS TRIGGERED BY EARLY LIFE ADVERSITY. LONGITUDINAL EPIDEMIOLOGICAL STUDIES WITH BIRTH COHORTS HAVE SHOWN THAT PHYSICAL AGGRESSION IN HUMANS DOES NOT APPEAR SUDDENLY IN ADOLESCENCE AS COMMONLY THOUGHT. IN FACT, PHYSICALLY AGGRESSIVE BEHAVIOUR IS OBSERVED AS EARLY AS 12 MONTHS AFTER BIRTH, ITS FREQUENCY PEAKS AROUND 2-4 YEARS OF AGE AND DECREASES IN FREQUENCY UNTIL EARLY ADULTHOOD. HOWEVER, A MINORITY OF CHILDREN (3-7%) MAINTAIN A HIGH FREQUENCY OF PHYSICAL AGGRESSION FROM CHILDHOOD TO ADOLESCENCE AND DEVELOP SERIOUS SOCIAL ADJUSTMENT PROBLEMS DURING ADULTHOOD. GENETIC FACTORS AND EARLY SOCIAL EXPERIENCES, AS WELL AS THEIR INTERACTION, HAVE BEEN SHOWN TO PLAY AN IMPORTANT ROLE IN THE DEVELOPMENT OF CHRONIC AGGRESSIVE BEHAVIOUR. HOWEVER, THE BIOLOGICAL MECHANISMS UNDERLYING THESE ASSOCIATIONS ARE JUST BEGINNING TO BE UNCOVERED. RECENT EVIDENCE SUGGESTS THAT EPIGENETIC MECHANISMS ARE RESPONSIVE TO ADVERSE ENVIRONMENTS AND COULD BE INVOLVED IN THE DEVELOPMENT OF CHRONIC AGGRESSION. USING BOTH GENE CANDIDATE AND GENOMIC APPROACHES, RECENT STUDIES HAVE IDENTIFIED EPIGENETIC MARKS, SUCH AS DNA METHYLATION ALTERATIONS IN GENES INVOLVED IN THE STRESS RESPONSE AND THE SEROTONIN AND IMMUNE SYSTEMS TO BE PARTLY RESPONSIBLE FOR THE LONG-LASTING EFFECTS OF EARLY ADVERSITY. FURTHER LONGITUDINAL STUDIES WITH BIOLOGICAL, ENVIRONMENTAL AND BEHAVIOURAL ASSESSMENTS FROM BIRTH ONWARDS ARE NEEDED TO ELUCIDATE THE SEQUENCE OF EVENTS THAT LEADS TO THESE LONG-LASTING EPIGENETIC MARKS ASSOCIATED WITH EARLY ADVERSITY AND AGGRESSION. 2015 4 396 34 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 5 1324 42 DEOXYRIBONUCLEIC ACID (DNA) METHYLATION IN CHILDREN EXPOSED TO AIR POLLUTION: A POSSIBLE MECHANISM UNDERLYING RESPIRATORY HEALTH EFFECTS DEVELOPMENT. AIR POLLUTION IS A SUBSTANTIAL ENVIRONMENTAL THREAT TO CHILDREN AND ACTS AS ACUTE AND CHRONIC DISEASE RISK FACTORS ALIKE. SEVERAL STUDIES HAVE PREVIOUSLY EVALUATED EPIGENETIC MODIFICATIONS CONCERNING ITS EXPOSURE ACROSS VARIOUS LIFE STAGES. HOWEVER, FINDINGS ON EPIGENETIC MODIFICATIONS AS THE CONSEQUENCES OF AIR POLLUTION DURING CHILDHOOD ARE RATHER MINIMAL. THIS REVIEW EVALUATED HIGHLY RELEVANT STUDIES IN THE FIELD TO ANALYZE THE EXISTING LITERATURE REGARDING EXPOSURE TO AIR POLLUTION, WITH A FOCUS ON EPIGENETIC ALTERATIONS DURING CHILDHOOD AND THEIR CONNECTIONS WITH RESPIRATORY HEALTH EFFECTS. THE SEARCH WAS CONDUCTED USING READILY AVAILABLE ELECTRONIC DATABASES (PUBMED AND SCIENCEDIRECT) TO SCREEN FOR CHILDREN'S STUDIES ON EPIGENETIC MECHANISMS FOLLOWING EITHER PRE- OR POST-NATAL EXPOSURE TO AIR POLLUTANTS. STUDIES RELEVANT ENOUGH AND MATCHED THE PREDETERMINED CRITERIA WERE CHOSEN TO BE REVIEWED. NON-ENGLISH ARTICLES AND STUDIES THAT DID NOT REPORT BOTH AIR MONITORING AND EPIGENETIC OUTCOMES IN THE SAME ARTICLE WERE EXCLUDED. THE REVIEW FOUND THAT EPIGENETIC CHANGES HAVE BEEN LINKED WITH EXPOSURE TO AIR POLLUTANTS DURING EARLY LIFE WITH EVIDENCE AND REPORTS OF HOW THEY MAY DEREGULATE THE EPIGENOME BALANCE, THUS INDUCING DISEASE PROGRESSION IN THE FUTURE. EPIGENETIC STUDIES EVOLVE AS A PROMISING NEW APPROACH IN DECIPHERING THE UNDERLYING IMPACTS OF AIR POLLUTION ON DEOXYRIBONUCLEIC ACID (DNA) DUE TO LINKS ESTABLISHED BETWEEN SOME OF THESE EPIGENETIC MECHANISMS AND ILLNESSES. 2021 6 6159 40 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 7 1546 30 DNA METHYLATION IN NASAL EPITHELIUM: STRENGTHS AND LIMITATIONS OF AN EMERGENT BIOMARKER FOR CHILDHOOD ASTHMA. ASTHMA IS ONE OF THE MOST WIDESPREAD CHRONIC RESPIRATORY CONDITIONS. THIS DISEASE PRIMARILY DEVELOPS IN CHILDHOOD AND IS INFLUENCED BY DIFFERENT FACTORS, MAINLY GENETICS AND ENVIRONMENTAL FACTORS. DNA METHYLATION IS AN EPIGENETIC MECHANISM WHICH MAY REPRESENT A BRIDGE BETWEEN THESE TWO FACTORS, PROVIDING A TOOL TO COMPREHEND THE INTERACTION BETWEEN GENETICS AND ENVIRONMENT. MOST EPIDEMIOLOGICAL STUDIES IN THIS FIELD HAVE BEEN CONDUCTED USING BLOOD SAMPLES, ALTHOUGH DNA METHYLATION MARKS IN BLOOD MAY NOT BE RELIABLE FOR DRAWING EXHAUSTIVE CONCLUSIONS ABOUT DNA METHYLATION IN THE AIRWAYS. BECAUSE OF THE ROLE OF NASAL EPITHELIUM IN ASTHMA AND THE TISSUE SPECIFICITY OF DNA METHYLATION, STUDYING THE RELATIONSHIP BETWEEN DNA METHYLATION AND CHILDHOOD ASTHMA MIGHT REVEAL CRUCIAL INFORMATION ABOUT THIS WIDESPREAD RESPIRATORY DISEASE. THE PURPOSE OF THIS REVIEW IS TO DESCRIBE CURRENT FINDINGS IN THIS FIELD OF RESEARCH. WE WILL PRESENT A VIEWPOINT OF SELECTED STUDIES, CONSIDER STRENGTHS AND LIMITATIONS, AND PROPOSE FUTURE RESEARCH IN THIS AREA. 2020 8 2677 32 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 9 1765 33 EARLY-LIFE ADVERSITY-INDUCED LONG-TERM EPIGENETIC PROGRAMMING ASSOCIATED WITH EARLY ONSET OF CHRONIC PHYSICAL AGGRESSION: STUDIES IN HUMANS AND ANIMALS. OBJECTIVES: TO EXAMINE WHETHER CHRONIC PHYSICAL AGGRESSION (CPA) IN ADULTHOOD CAN BE EPIGENETICALLY PROGRAMMED EARLY IN LIFE DUE TO EXPOSURE TO EARLY-LIFE ADVERSITY. METHODS: LITERATURE SEARCH OF PUBLIC DATABASES SUCH AS PUBMED/MEDLINE AND SCOPUS. RESULTS: CHILDREN/ADOLESCENTS SUSCEPTIBLE FOR CPA AND EXPOSED TO EARLY-LIFE ABUSE FAIL TO EFFICIENTLY COPE WITH STRESS THAT IN TURN RESULTS IN THE DEVELOPMENT OF CPA LATER IN LIFE. THIS PHENOMENON WAS OBSERVED IN HUMANS AND ANIMAL MODELS OF AGGRESSION. THE SUSCEPTIBILITY TO AGGRESSION IS A COMPLEX TRAIT THAT IS REGULATED BY THE INTERACTION BETWEEN ENVIRONMENTAL AND GENETIC FACTORS. EPIGENETIC MECHANISMS MEDIATE THIS INTERACTION. SUBJECTS EXPOSED TO STRESS EARLY IN LIFE EXHIBITED LONG-TERM EPIGENETIC PROGRAMMING THAT CAN INFLUENCE THEIR BEHAVIOUR IN ADULTHOOD. THIS PROGRAMMING AFFECTS EXPRESSION OF MANY GENES NOT ONLY IN THE BRAIN BUT ALSO IN OTHER SYSTEMS SUCH AS NEUROENDOCRINE AND IMMUNE. CONCLUSIONS: THE PROPENSITY TO ADULT CPA BEHAVIOUR IN SUBJECTS EXPERIENCED TO EARLY-LIFE ADVERSITY IS MEDIATED BY EPIGENETIC PROGRAMMING THAT INVOLVES LONG-TERM SYSTEMIC EPIGENETIC ALTERATIONS IN A WHOLE GENOME. 2019 10 2530 33 EPIGENETICS IN ALLERGIC DISEASES. PURPOSE OF REVIEW: ALLERGIC DISEASES ARE AMONG THE MOST PREVALENT CHRONIC DISEASES OF CHILDHOOD, AFFECTING MORE THAN 7 MILLION CHILDREN IN THE UNITED STATES. EPIDEMIOLOGICAL EVIDENCE SUPPORTS THE IDEA THAT THE INCEPTION OF ALLERGIC DISEASES IS TYPICALLY BEFORE THE PRESCHOOL YEARS, EVEN WHEN CHRONIC SYMPTOMS DO NOT EMERGE UNTIL ADULTHOOD. THE ROLE OF EPIGENETIC MECHANISMS (PARTICULARLY DNA METHYLATION) IN ALLERGIC DISEASE IS UNDER ACTIVE INVESTIGATION BECAUSE THESE MECHANISMS ARE KNOWN TO BE AT THE INTERFACE OF GENE REGULATION, ENVIRONMENTAL STIMULI, AND DEVELOPMENTAL PROCESSES, ALL OF WHICH ARE ESSENTIAL FOR THE PATHOGENESIS FOR ASTHMA AND ALLERGY. THIS ARTICLE SPECIFICALLY REVIEWS GENOME-WIDE DNA METHYLATION STUDIES IN ALLERGIC DISEASE. RECENT FINDINGS: DIFFERENTIAL DNA METHYLATION AT SPECIFIC REGIONS APPEARS TO BE ASSOCIATED WITH CONCURRENT ALLERGIC DISEASE. A FEW STUDIES HAVE IDENTIFIED METHYLATION SIGNATURES PREDICTIVE OF DISEASE. SUMMARY: DNA METHYLATION SIGNATURES HAVE BEEN SHOWN TO BE ASSOCIATED WITH SEVERAL ALLERGIC DISEASE PHENOTYPES, TYPICALLY CONCURRENTLY WITH DISEASE. THE FEW THAT HAVE BEEN FOUND TO PRECEDE DIAGNOSIS ARE ESPECIALLY INTERESTING BECAUSE THEY HIGHLIGHT AN EARLY TRAJECTORY TO DISEASE. 2015 11 2651 31 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 12 2160 24 EPIGENETIC MECHANISMS IN ASTHMA. ASTHMA AND ALLERGIC DISEASES ARE AMONG THE MOST PREVALENT CHRONIC NONCOMMUNICABLE DISEASES OF CHILDHOOD, BUT THE UNDERLYING PATHOGENETIC MECHANISMS ARE POORLY UNDERSTOOD. BECAUSE EPIGENETIC MECHANISMS LINK GENE REGULATION TO ENVIRONMENTAL CUES AND DEVELOPMENTAL TRAJECTORIES, THEIR CONTRIBUTION TO ASTHMA AND ALLERGY PATHOGENESIS IS UNDER ACTIVE INVESTIGATION. DNA METHYLATION SIGNATURES ASSOCIATED WITH CONCURRENT DISEASE AND WITH THE DEVELOPMENT OF ASTHMA DURING CHILDHOOD ASTHMA HAVE BEEN IDENTIFIED, BUT THEIR SIGNIFICANCE IS NOT EASILY INTERPRETABLE. ON THE OTHER HAND, THE CHARACTERIZATION OF EARLY EPIGENETIC PREDICTORS OF ASTHMA POINTS TO A POTENTIAL ROLE OF EPIGENETIC MECHANISMS IN REGULATING THE INCEPTION OF, AND THE SUSCEPTIBILITY TO, THIS DISEASE. 2016 13 1736 34 EARLY DETECTION AND PREVENTION OF SCHIZOPHRENIC PSYCHOSIS-A REVIEW. PSYCHOTIC DISORDERS OFTEN RUN A CHRONIC COURSE AND ARE ASSOCIATED WITH A CONSIDERABLE EMOTIONAL AND SOCIAL IMPACT FOR PATIENTS AND THEIR RELATIVES. THEREFORE, EARLY RECOGNITION, COMBINED WITH THE POSSIBILITY OF PREVENTIVE INTERVENTION, IS URGENTLY WARRANTED SINCE THE DURATION OF UNTREATED PSYCHOSIS (DUP) SIGNIFICANTLY DETERMINES THE FURTHER COURSE OF THE DISEASE. IN ADDITION TO ESTABLISHED DIAGNOSTIC TOOLS, NEUROBIOLOGICAL FACTORS IN THE DEVELOPMENT OF SCHIZOPHRENIC PSYCHOSES ARE INCREASINGLY BEING INVESTIGATED. IT IS SHOWN THAT NUMEROUS MOLECULAR ALTERATIONS ALREADY EXIST BEFORE THE CLINICAL ONSET OF THE DISEASE. AS SCHIZOPHRENIC PSYCHOSES ARE NOT ELICITED BY A SINGLE MUTATION IN THE DEOXYRIBONUCLEIC ACID (DNA) SEQUENCE, EPIGENETICS LIKELY CONSTITUTE THE MISSING LINK BETWEEN ENVIRONMENTAL INFLUENCES AND DISEASE DEVELOPMENT AND COULD POTENTIALLY SERVE AS A BIOMARKER. THE RESULTS FROM TRANSCRIPTOMIC AND PROTEOMIC STUDIES POINT TO A DYSREGULATED IMMUNE SYSTEM, LIKELY EVOKED BY EPIGENETIC ALTERATIONS. DESPITE THE INCREASING KNOWLEDGE OF THE NEUROBIOLOGICAL MECHANISMS INVOLVED IN THE DEVELOPMENT OF PSYCHOTIC DISORDERS, FURTHER RESEARCH EFFORTS WITH LARGE POPULATION-BASED STUDY DESIGNS ARE NEEDED TO IDENTIFY SUITABLE BIOMARKERS. IN CONCLUSION, A COMBINATION OF BLOOD EXAMINATIONS, FUNCTIONAL IMAGING TECHNIQUES, ELECTROENCEPHALOGRAPHY (EEG) INVESTIGATIONS AND POLYGENIC RISK SCORES SHOULD BE CONSIDERED AS THE BASIS FOR PREDICTING HOW SUBJECTS WILL TRANSITION INTO MANIFEST PSYCHOSIS. 2021 14 2075 39 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 15 1203 32 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 16 2917 25 GENE-ENVIRONMENT INTERACTIONS IN COMMON MENTAL DISORDERS: AN UPDATE AND STRATEGY FOR A GENOME-WIDE SEARCH. A DECADE OF RESEARCH HAS DEMONSTRATED THE EXPLANATORY POTENTIAL OF INTERPLAY BETWEEN GENETIC VARIANTS AND ENVIRONMENTAL FACTORS IN THE DEVELOPMENT OF COMMON MENTAL DISORDERS. INITIAL FINDINGS HAVE UNDERGONE TESTS OF REPLICABILITY AND SPECIFICITY. SOME GENE-ENVIRONMENT INTERACTIONS HAVE BEEN CONFIRMED, SOME HAVE NOT REPLICATED AND YET OTHER TURNED OUT TO BE MORE SPECIFIC THAN INITIALLY THOUGHT. SPECIFIC AND COMPLEMENTARY ROLES OF GENETIC FACTORS HAVE BEEN DELINEATED: A COMMON FUNCTIONAL LENGTH POLYMORPHISM IN THE SEROTONIN TRANSPORTER GENE (5-HTTLPR) MODERATED THE EFFECT OF CHILDHOOD MALTREATMENT ON CHRONIC DEPRESSION IN ADULTHOOD, BUT DID NOT SUBSTANTIALLY INFLUENCE THE EFFECTS OF ADULT STRESSFUL LIFE EVENTS ON THE ONSET OF NEW DEPRESSIVE EPISODES; IN CONTRAST, A COMMON FUNCTIONAL POLYMORPHISM IN THE BRAIN-DERIVED NEUROTROPHIC FACTOR GENE (BDNF) MODERATED THE EFFECT OF STRESSFUL LIFE EVENTS IN ADULTHOOD IN TRIGGERING NEW DEPRESSIVE EPISODES, BUT DID NOT INFLUENCE THE EFFECTS OF CHILDHOOD MALTREATMENT. MOLECULAR MECHANISMS UNDERLYING GENE-ENVIRONMENT INTERACTIONS ARE BEING UNCOVERED, INCLUDING DNA METHYLATION AND OTHER EPIGENETIC MODIFICATIONS. NEW GENE-ENVIRONMENT INTERACTIONS CONTINUE TO BE REPORTED, STILL LARGELY FROM HYPOTHESIS-DRIVEN RESEARCH. STATISTICAL AND BIOLOGICAL PRIORITIZATION STRATEGIES ARE PROPOSED TO FACILITATE A SYSTEMATIC DISCOVERY OF NOVEL GENE-ENVIRONMENT INTERACTIONS IN GENOME-WIDE ANALYSES. 2014 17 5164 38 PRECLINICAL AND CLINICAL EVIDENCE OF DNA METHYLATION CHANGES IN RESPONSE TO TRAUMA AND CHRONIC STRESS. EXPOSURE TO CHRONIC STRESS, EITHER REPEATED SEVERE ACUTE OR MODERATE SUSTAINED STRESS, IS ONE OF THE STRONGEST RISK FACTORS FOR THE DEVELOPMENT OF PSYCHOPATHOLOGIES SUCH AS POST-TRAUMATIC STRESS DISORDER AND DEPRESSION. CHRONIC STRESS IS LINKED WITH SEVERAL LASTING BIOLOGICAL CONSEQUENCES, PARTICULARLY TO THE STRESS ENDOCRINE SYSTEM BUT ALSO AFFECTING INTERMEDIATE PHENOTYPES SUCH AS BRAIN STRUCTURE AND FUNCTION, IMMUNE FUNCTION, AND BEHAVIOR. ALTHOUGH GENETIC PREDISPOSITION CONFERS A PROPORTION OF THE RISK, THE MOST RELEVANT MOLECULAR MECHANISMS DETERMINING THOSE SUSCEPTIBLE AND RESILIENT TO THE EFFECTS OF STRESS AND TRAUMA MAY BE EPIGENETIC. EPIGENETICS REFERS TO THE MECHANISMS THAT REGULATE GENOMIC INFORMATION BY DYNAMICALLY CHANGING THE PATTERNS OF TRANSCRIPTION AND TRANSLATION OF GENES. MOUNTING EVIDENCE FROM PRECLINICAL RODENT AND CLINICAL POPULATION STUDIES STRONGLY SUPPORT THAT EPIGENETIC MODIFICATIONS CAN OCCUR IN RESPONSE TO TRAUMATIC AND CHRONIC STRESS. HERE, WE DISCUSS THIS LITERATURE EXAMINING STRESS-INDUCED EPIGENETIC CHANGES IN PRECLINICAL MODELS AND CLINICAL COHORTS OF STRESS AND TRAUMA OCCURRING EARLY IN LIFE OR IN ADULTHOOD. WE HIGHLIGHT THAT A COMPLEX RELATIONSHIP BETWEEN THE TIMING OF ENVIRONMENTAL STRESSORS AND GENETIC PREDISPOSITIONS LIKELY MEDIATE THE RESPONSE TO CHRONIC STRESS OVER TIME, AND THAT A BETTER UNDERSTANDING OF EPIGENETIC CHANGES IS NEEDED BY FURTHER INVESTIGATIONS IN LONGITUDINAL AND POSTMORTEM BRAIN CLINICAL COHORTS. 2017 18 2213 44 EPIGENETIC MODIFICATIONS AS OUTCOMES OF EXERCISE INTERVENTIONS RELATED TO SPECIFIC METABOLIC ALTERATIONS: A SYSTEMATIC REVIEW. BACKGROUND: CHRONIC DISEASES ARISE AS A CONSEQUENCE OF AN UNHEALTHY LIFESTYLE PRIMARILY CHARACTERIZED BY PHYSICAL INACTIVITY AND UNBALANCED DIETS. REGULAR PHYSICAL ACTIVITY CAN IMPROVE HEALTH, AND THERE IS CONSISTENT EVIDENCE THAT THESE IMPROVEMENTS MAY BE THE RESULT OF EPIGENETIC MODIFICATIONS. OBJECTIVE: TO IDENTIFY EPIGENETIC MODIFICATIONSAS OUTCOMES OF EXERCISE INTERVENTIONS RELATED TO SPECIFIC METABOLIC ALTERATIONS. METHODS: THE PREFERRED REPORTING ITEMS FOR SYSTEMATIC REVIEWS AND META-ANALYSES PROTOCOLS (PRISMA-P) METHODOLOGY FOR MANUSCRIPT RESEARCH AND PREPARATION WAS FOLLOWED USING PUBMED AND EBSCO DATABASES FOR LITERATURE REVIEW. OUT OF 2,638 ARTICLES IDENTIFIED, ONLY 34 ARTICLES MET THE INCLUSION CRITERIA. RESULTS: THE SECTIONS OF THE REVIEW WERE ORGANIZED BY METABOLIC ALTERATIONS IN WHICH STUDIES WERE GROUPED ACCORDING TO HEALTHY, DISEASED, AND TRAINED INDIVIDUALS. RESISTANCE EXERCISE IN HUMANS INDUCED EPIGENETIC CHANGES IN PATHWAYS ASSOCIATED WITH ENERGY METABOLISM AND INSULIN SENSITIVITY, CONTRIBUTING TO HEALTHY SKELETAL MUSCLE. ENDURANCE EXERCISE ALSO CAUSED MODIFICATIONS IN BIOMARKERS ASSOCIATED TO METABOLIC ALTERATIONS THROUGH CHANGES IN DNA METHYLATION AND THE EXPRESSION OF SPECIFIC MIRNAS. HOWEVER, BOTH RESISTANCE AND ENDURANCE EXERCISE ARE NECESSARY TO OBTAIN A BETTER PHYSIOLOGICAL ADAPTATION AND A COMBINATION OF BOTH SEEMS TO BE NEEDED TO PROPERLY TACKLE THE INCREASING PREVALENCE OF NON-COMMUNICABLE PATHOLOGIES. CONCLUSION: GIVEN THE HETEROGENEITY AND COMPLEXITY OF THE EXISTING LITERATURE, IT IS CURRENTLY NOT POSSIBLE TO PROPOSE A SPECIFIC RECOMMENDATION ABOUT THE TYPE, INTENSITY, OR DURATION OF EXERCISE THAT COULD BE BENEFICIAL FOR DIFFERENT SUBSETS OF THE POPULATION (HEALTHY, DISEASED, AND/OR TRAINED). NEVERTHELESS, THIS REVIEW HIGHLIGHTS THE IMPORTANCE OF EXERCISE FOR HEALTH AND SHOWS THE NEED TO PERFORM MORE RESEARCH IN THIS EMERGING AREA TO IDENTIFY EPIGENETIC BIOMARKERS THAT COULD SERVE AS INDICATORS OF EXERCISE ADAPTATIONS. 2019 19 6823 25 [GENERAL CONCEPTS OF EPIGENETICS: PROJECTIONS IN PAEDIATRICS]. CURRENT EVIDENCE SUPPORTS THE NOTION THAT ALTERATIONS IN INTRAUTERINE GROWTH AND DURING THE FIRST YEARS OF LIFE HAVE A SUBSTANTIAL EFFECT ON THE RISK FOR THE DEVELOPMENT OF CHRONIC DISEASE, WHICH IN SOME CASES IS EVEN HIGHER THAN THOSE DUE TO GENETIC FACTORS. THE PERSISTENCE AND REPRODUCIBILITY OF THE PHENOTYPES ASSOCIATED WITH ALTERED EARLY DEVELOPMENT SUGGEST THE PARTICIPATION OF MECHANISMS THAT WOULD RECORD ENVIRONMENTAL CUES, GENERATING A CELLULAR REPROGRAMMING (I.E., EPIGENETIC MECHANISMS). THIS REVIEW IS AN INTRODUCTION TO A SERIES OF FIVE ARTICLES FOCUSED ON THE PARTICIPATION OF EPIGENETIC MECHANISMS IN THE DEVELOPMENT OF HIGHLY PREVALENT CHRONIC DISEASES (I.E., CARDIOVASCULAR, METABOLIC, ASTHMA/ALLERGIES AND CANCER) AND THEIR ORIGINS IN THE FOETAL AND NEONATAL PERIOD. THIS SERIES OF ARTICLES AIMS TO SHOW THE STATE OF THE ART IN THIS RESEARCH AREA AND PRESENT THE UPCOMING CLUES AND CHALLENGES, IN WHICH PAEDIATRICIANS HAVE A PROMINENT ROLE, DEVELOPING STRATEGIES FOR THE PREVENTION, EARLY DETECTION AND FOLLOW-UP. 2016 20 1014 28 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