1 3032 134 GENETICS OF TINNITUS: AN EMERGING AREA FOR MOLECULAR DIAGNOSIS AND DRUG DEVELOPMENT. SUBJECTIVE TINNITUS IS THE PERCEPTION OF SOUND IN THE ABSENCE OF EXTERNAL OR BODILY-GENERATED SOUNDS. CHRONIC TINNITUS IS A HIGHLY PREVALENT CONDITION AFFECTING OVER 70 MILLION PEOPLE IN EUROPE. A WIDE VARIETY OF COMORBIDITIES, INCLUDING HEARING LOSS, PSYCHIATRIC DISORDERS, NEURODEGENERATIVE DISORDERS, AND TEMPOROMANDIBULAR JOINT (TMJ) DYSFUNCTION, HAVE BEEN SUGGESTED TO CONTRIBUTE TO THE ONSET OR PROGRESSION OF TINNITUS; HOWEVER, THE PRECISE MOLECULAR MECHANISMS OF TINNITUS ARE NOT WELL UNDERSTOOD AND THE CONTRIBUTION OF GENETIC AND EPIGENETIC FACTORS REMAINS UNKNOWN. HUMAN GENETIC STUDIES COULD ENABLE THE IDENTIFICATION OF NOVEL MOLECULAR THERAPEUTIC TARGETS, POSSIBLY LEADING TO THE DEVELOPMENT OF NOVEL PHARMACEUTICAL THERAPEUTICS. IN THIS ARTICLE, WE BRIEFLY DISCUSS THE AVAILABLE EVIDENCE FOR A ROLE OF GENETICS IN TINNITUS AND CONSIDER POTENTIAL HURDLES IN DESIGNING GENETIC STUDIES FOR TINNITUS. SINCE MULTIPLE DISEASES HAVE TINNITUS AS A SYMPTOM AND THE SUPPORTING GENETIC EVIDENCE IS SPARSE, WE PROPOSE VARIOUS STRATEGIES TO INVESTIGATE THE GENETIC UNDERPINNINGS OF TINNITUS, FIRST BY SHOWING EVIDENCE OF HERITABILITY USING CONCORDANCE STUDIES IN TWINS, AND SECOND BY IMPROVING PATIENT SELECTION ACCORDING TO PHENOTYPE AND/OR ETIOLOGY IN ORDER TO CONTROL POTENTIAL BIASES AND OPTIMIZE GENETIC DATA OUTPUT. THE INCREASED KNOWLEDGE RESULTING FROM THIS ENDEAVOR COULD ULTIMATELY IMPROVE THE DRUG DEVELOPMENT PROCESS AND LEAD TO THE PREVENTIVE OR CURATIVE TREATMENT OF TINNITUS. 2016 2 2526 41 EPIGENETICS APPLIED TO PSYCHIATRY: CLINICAL OPPORTUNITIES AND FUTURE CHALLENGES. PSYCHIATRIC DISORDERS ARE CLINICALLY HETEROGENEOUS AND DEBILITATING CHRONIC DISEASES RESULTING FROM A COMPLEX INTERPLAY BETWEEN GENE VARIANTS AND ENVIRONMENTAL FACTORS. EPIGENETIC PROCESSES, SUCH AS DNA METHYLATION AND HISTONE POSTTRANSLATIONAL MODIFICATIONS, INSTRUCT THE CELL/TISSUE TO CORRECTLY INTERPRET EXTERNAL SIGNALS AND ADJUST ITS FUNCTIONS ACCORDINGLY. GIVEN THAT EPIGENETIC MODIFICATIONS ARE SENSITIVE TO ENVIRONMENT, STABLE, AND REVERSIBLE, EPIGENETIC STUDIES IN PSYCHIATRY COULD REPRESENT A PROMISING APPROACH TO BETTER UNDERSTANDING AND TREATING DISEASE. IN THE PRESENT REVIEW, WE AIM TO DISCUSS THE CLINICAL OPPORTUNITIES AND CHALLENGES ARISING FROM THE EPIGENETIC RESEARCH IN PSYCHIATRY. USING SELECTED EXAMPLES, WE FIRST RECAPITULATE KEY FINDINGS SUPPORTING THE ROLE OF ADVERSE LIFE EVENTS, ALONE OR IN COMBINATION WITH GENETIC RISK, IN EPIGENETIC PROGRAMMING OF NEUROPSYCHIATRIC SYSTEMS. EPIGENETIC STUDIES FURTHER REPORT ENCOURAGING FINDINGS ABOUT THE USE OF METHYLATION CHANGES AS DIAGNOSTIC MARKERS OF DISEASE PHENOTYPE AND PREDICTIVE TOOLS OF PROGRESSION AND RESPONSE TO TREATMENT. THEN WE DISCUSS THE POTENTIAL OF USING TARGETED EPIGENETIC PHARMACOTHERAPY, COMBINED WITH PSYCHOSOCIAL INTERVENTIONS, FOR FUTURE PERSONALIZED MEDICINE FOR PATIENTS. FINALLY, WE REVIEW THE METHODOLOGICAL LIMITATIONS THAT COULD HINDER INTERPRETATION OF EPIGENETIC DATA IN PSYCHIATRY. THEY MAINLY ARISE FROM HETEROGENEITY AT THE INDIVIDUAL AND TISSUE LEVEL AND REQUIRE FUTURE STRATEGIES IN ORDER TO REINFORCE THE BIOLOGICAL RELEVANCE OF EPIGENETIC DATA AND ITS TRANSLATIONAL USE IN PSYCHIATRY. OVERALL, WE SUGGEST THAT EPIGENETICS COULD PROVIDE NEW INSIGHTS INTO A MORE COMPREHENSIVE INTERPRETATION OF MENTAL ILLNESS AND MIGHT EVENTUALLY IMPROVE THE NOSOLOGY, TREATMENT, AND PREVENTION OF PSYCHIATRIC DISORDERS. 2018 3 2963 31 GENETIC AND EPIGENETIC MECHANISMS LINKING PAIN AND PSYCHIATRIC DISORDERS. THE NEUROPHYSIOLOGICAL LINK BETWEEN NEUROPATHIC PAIN AND DEPRESSION REMAINS UNKNOWN DESPITE EVIDENT HIGH COMORBIDITY OF THESE TWO DISORDERS. HOWEVER, THERE IS CONVINCING EVIDENCE THAT GENOTYPE PLAYS A ROLE IN BOTH PAIN AND DEPRESSION. USING VARIOUS TYPES OF GENETIC ANALYSIS - POPULATION GENETICS, CYTOGENETICS AND MOLECULAR TECHNOLOGIES - SPECIFIC GENES HAVE BEEN IMPLICATED IN MEDIATING ALMOST ALL ASPECTS OF NOCICEPTION AND MOOD DISORDERS. THE CURRENT REVIEW ATTEMPTS TO IDENTIFY SPECIFIC GENES AND EPIGENETIC MECHANISMS COMMON TO BOTH DISORDERS. IT IS CONCLUDED THAT EXTERNAL AND INTERNAL FACTORS (INFLAMMATION, STRESS, GENDER, ETC.) THAT CONTRIBUTE TO THE PATHOLOGIES MAY DO SO THROUGH EPIGENETIC MECHANISMS THAT MAY AFFECT EXPRESSION OF THESE PARTICULAR GENES. THE POSSIBLE INVOLVEMENT OF EPIGENETIC REGULATION IN PAIN AND PSYCHIATRIC DISORDERS SUGGESTS THAT TREATMENTS TARGETING EPIGENETIC MECHANISMS THAT MEDIATE ADVERSE LIFE EVENTS SHOULD BE CONSIDERED. 2015 4 2107 32 EPIGENETIC FACTORS IN SCHIZOPHRENIA: MECHANISMS AND EXPERIMENTAL APPROACHES. SCHIZOPHRENIA IS A CHRONIC MENTAL DISORDER THAT IS STILL POORLY UNDERSTOOD DESPITE DECADES OF STUDY. MANY FACTORS HAVE BEEN FOUND TO CONTRIBUTE TO THE PATHOGENESIS, INCLUDING NEURODEVELOPMENTAL DISTURBANCE, GENETIC RISK, AND ENVIRONMENTAL INSULT, BUT NO SINGLE ROOT CAUSE HAS EMERGED. WHILE EVIDENCE FROM TWIN STUDIES SUGGESTS A STRONG HERITABLE COMPONENT, FEW INDIVIDUAL LOCI HAVE BEEN IDENTIFIED IN GENOMEWIDE SCREENS, SUGGESTING A ROLE FOR EPIGENETIC EFFECTS. RATHER, LARGE NUMBERS OF WEAKLY ACTING LOCI MAY CUMULATIVELY INCREASE DISEASE RISK, INCLUDING SEVERAL MAPPING TO EPIGENETIC PATHWAYS. IN THIS REVIEW, WE DISCUSS MECHANISMS OF EPIGENETIC REGULATION AND EVIDENCE FOR AN EPIGENETIC CONTRIBUTION TO DISEASE PHENOTYPE. WE FURTHER DESCRIBE THE RANGE OF EXPERIMENTAL TOOLS CURRENTLY AVAILABLE TO STUDY EPIGENETIC EFFECTS ASSOCIATED WITH THE DISEASE. 2019 5 6260 30 THE MOLECULAR NEUROBIOLOGY OF CHRONIC PAIN-INDUCED DEPRESSION. THE INCREASING NUMBER OF INDIVIDUALS WITH COMORBIDITIES POSES AN URGENT NEED TO IMPROVE THE MANAGEMENT OF PATIENTS WITH MULTIPLE CO-EXISTING DISEASES. AMONG THESE COMORBIDITIES, CHRONIC PAIN AND MOOD DISORDERS, TWO LONG-LASTING DISABLING CONDITIONS THAT SIGNIFICANTLY REDUCE THE QUALITY OF LIFE, COULD BE CITED FIRST. THE RECENT DEVELOPMENT OF ANIMAL MODELS ACCELERATED THE STUDIES FOCUSING ON THE UNDERLYING MECHANISMS OF THE CHRONIC PAIN AND DEPRESSION/ANXIETY COMORBIDITY. THIS REVIEW PROVIDES AN OVERVIEW OF CLINICAL AND PRE-CLINICAL STUDIES PERFORMED OVER THE PAST TWO DECADES ADDRESSING THE MOLECULAR ASPECTS OF THE COMORBID RELATIONSHIP OF CHRONIC PAIN AND DEPRESSION. WE THUS FOCUSED ON THE STUDIES THAT INVESTIGATED THE MOLECULAR CHARACTERISTICS OF THE COMORBID RELATIONSHIP BETWEEN CHRONIC PAIN AND MOOD DISORDERS, ESPECIALLY MAJOR DEPRESSIVE DISORDERS, FROM THE GENETIC AND EPIGENETIC POINT OF VIEW TO KEY NEUROMODULATORS WHICH HAVE BEEN SHOWN TO PLAY AN IMPORTANT ROLE IN THIS COMORBIDITY. 2019 6 2404 37 EPIGENETIC RESEARCH IN MULTIPLE SCLEROSIS: PROGRESS, CHALLENGES, AND OPPORTUNITIES. MULTIPLE SCLEROSIS (MS) IS A CHRONIC INFLAMMATORY AND DEMYELINATING DISEASE OF THE CENTRAL NERVOUS SYSTEM. MS LIKELY RESULTS FROM A COMPLEX INTERPLAY BETWEEN PREDISPOSING CAUSAL GENE VARIANTS (THE STRONGEST INFLUENCE COMING FROM HLA CLASS II LOCUS) AND ENVIRONMENTAL RISK FACTORS SUCH AS SMOKING, INFECTIOUS MONONUCLEOSIS, AND LACK OF SUN EXPOSURE/VITAMIN D. HOWEVER, LITTLE IS KNOWN ABOUT THE MECHANISMS UNDERLYING MS DEVELOPMENT AND PROGRESSION. MOREOVER, THE CLINICAL HETEROGENEITY AND VARIABLE RESPONSE TO TREATMENT REPRESENT ADDITIONAL CHALLENGES TO A COMPREHENSIVE UNDERSTANDING AND EFFICIENT TREATMENT OF DISEASE. EPIGENETIC PROCESSES, SUCH AS DNA METHYLATION AND HISTONE POSTTRANSLATIONAL MODIFICATIONS, INTEGRATE INFLUENCES FROM THE GENES AND THE ENVIRONMENT TO REGULATE GENE EXPRESSION ACCORDINGLY. STUDYING EPIGENETIC MODIFICATIONS, WHICH ARE STABLE AND REVERSIBLE, MAY PROVIDE AN ALTERNATIVE APPROACH TO BETTER UNDERSTAND AND MANAGE DISEASE. WE HERE AIM TO REVIEW FINDINGS FROM EPIGENETIC STUDIES IN MS AND FURTHER DISCUSS THE CHALLENGES AND CLINICAL OPPORTUNITIES ARISING FROM EPIGENETIC RESEARCH, MANY OF WHICH APPLY TO OTHER DISEASES WITH SIMILAR COMPLEX ETIOLOGY. A GROWING BODY OF EVIDENCE SUPPORTS A ROLE OF EPIGENETIC PROCESSES IN THE MECHANISMS UNDERLYING IMMUNE PATHOGENESIS AND NERVOUS SYSTEM DYSFUNCTION IN MS. HOWEVER, DISPARITIES BETWEEN STUDIES SHED LIGHT ON THE NEED TO CONSIDER POSSIBLE CONFOUNDERS AND METHODOLOGICAL LIMITATIONS FOR A BETTER INTERPRETATION OF THE DATA. NEVERTHELESS, TRANSLATIONAL USE OF EPIGENETICS MIGHT OFFER NEW OPPORTUNITIES IN EPIGENETIC-BASED DIAGNOSTICS AND THERAPEUTIC TOOLS FOR A PERSONALIZED CARE OF MS PATIENTS. 2017 7 1736 32 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 8 6863 28 [ONE AUTISM, SEVERAL AUTISMS. PHENOTYPICAL VARIABILITY IN AUTISM SPECTRUM DISORDERS]. INTRODUCTION: AUTISM SPECTRUM DISORDERS (ASD) ARE A HETEROGENEOUS GROUP OF DISORDERS THAT BEGIN IN THE EARLY MONTHS OF LIFE AND FOLLOW A CHRONIC PROGRESSION. THEY HAVE A BIOLOGICAL ORIGIN, WITH COMPLEX AETIOLOGICAL FACTORS THAT INVOLVE DIFFERENT GENETIC, EPIGENETIC AND ENVIRONMENTAL MECHANISMS THAT INTERACT WITH ONE ANOTHER. AIM: TO REVIEW THE MAIN FACTORS THAT VARY THE PRESENTATION OF AUTISM TAKING INTO ACCOUNT THE MOST RECENT SCIENTIFIC EVIDENCE. DEVELOPMENT: ASPECTS RELATED WITH THE DEVELOPMENT OF SYMPTOMS, GENDER, COMORBIDITY, AGE AND AETIOLOGY DETERMINE THE VARIABILITY IN THE CLINICAL PRESENTATION OF ASD. CONCLUSIONS: AUTISM IS HIGHLY HETEROGENEOUS AND IS PHENOTYPICALLY RELATED, AT LEAST IN PART, WITH A WIDE RANGE OF CAUSATIONS, WHICH RESEARCHERS HAVE BEGUN TO UNRAVEL BUT WHICH ARE STILL LARGELY UNKNOWN. AETIOLOGICAL RESEARCH, ESPECIALLY IN THE AREA OF GENETICS, WILL MAKE IT POSSIBLE TO IDENTIFY DIFFERENT HOMOGENEOUS SUBGROUPS WITH THEIR CORRESPONDING PHENOTYPES, WHILE ALSO OPENING UP THE WAY TO POSSIBLE THERAPEUTIC ALTERNATIVES IN THE FUTURE. 2016 9 6676 31 USING EPIGENETIC TOOLS TO INVESTIGATE ANTIDEPRESSANT RESPONSE. MAJOR DEPRESSIVE DISORDER IS A CHRONIC AND DEBILITATING ILLNESS. IT IS MOST COMMONLY TREATED WITH ANTIDEPRESSANT DRUGS, HOWEVER, AS THE MAJORITY OF PATIENTS DO NOT RESPOND ON THEIR FIRST TRIAL OR FOLLOWING SEVERAL ADEQUATE TRIALS, THERE IS GREAT INTEREST IN IDENTIFYING BIOLOGICAL FACTORS THAT MAY HELP SELECT THE MOST APPROPRIATE TREATMENT FOR EACH PATIENT AND IN UNDERSTANDING BIOLOGICAL PROCESSES THAT MEDIATE TREATMENT RESPONSE. EPIGENETIC FACTORS, SUCH AS NON-CODING RNAS (NCRNAS), HOLD POTENTIAL AS BIOMARKERS OF ANTIDEPRESSANT RESPONSE. IN THIS CHAPTER, WE REVIEW KEY METHODOLOGICAL CONSIDERATIONS WHEN INVESTIGATING NCRNA BIOMARKERS, INCLUDING BIOLOGICAL SAMPLES AND TECHNOLOGIES WHICH HAVE BEEN USED IN THESE STUDIES. SECONDLY, WE SUMMARIZE FINDINGS FROM STUDIES INVESTIGATING NCRNAS IN ANTIDEPRESSANT TREATMENT RESPONSE. FINALLY, WE DISCUSS SOME OF THE FUTURE DIRECTIONS WHICH WILL BE NECESSARY FOR THE DEVELOPMENT OF CLINICALLY RELEVANT EPIGENETIC TOOLS. 2018 10 3108 31 GENOMICS OF PAIN IN OSTEOARTHRITIS. OSTEOARTHRITIS (OA) ACCOUNTS FOR THE MAJORITY OF THE DISEASE BURDEN FOR MUSCULOSKELETAL DISORDERS AND IS ONE OF THE LEADING CAUSES OF DISABILITY WORLDWIDE. THIS DISABILITY IS THE RESULT NOT OF THE CARTILAGE LOSS THAT DEFINES OA RADIOGRAPHICALLY, BUT OF THE CHRONIC PAIN WHOSE PRESENCE DEFINES SYMPTOMATIC OA. IT IS BECOMING CLEAR THAT MANY GENES, EACH WITH A SMALL EFFECT SIZE, CONTRIBUTE TO THE RISK OF DEVELOPING OA. HOWEVER, THE GENETICS OF OA PAIN ARE ONLY JUST STARTING TO BE EXPLORED. THIS REVIEW WILL DESCRIBE THE FIRST GENES TO HAVE BEEN IDENTIFIED IN GENOMIC STUDIES OF OA PAIN, AS WELL AS THE POSSIBLE DUAL ROLES OF GENES PREVIOUSLY IDENTIFIED IN GENOMIC STUDIES OF OA IN THE CONTEXT OF PAIN. DIFFICULTIES ASSOCIATED WITH ATTEMPTING TO CHARACTERISE THE GENETICS OF OA PAIN WILL BE DISCUSSED AND PROMISING FUTURE AVENUES OF RESEARCH INTO GENETIC AND EPIGENETIC FACTORS AFFECTING OA PAIN DESCRIBED. 2013 11 3016 37 GENETICS AND EPIGENETICS OF IBD. INFLAMMATORY BOWEL DISEASES (IBD) ARE CHRONIC INTERMITTENT INFLAMMATORY DISORDERS OF THE GASTROINTESTINAL TRACT OF UNKNOWN ETIOLOGY BUT A CLEAR GENETIC PREDISPOSITION. PROMPTED BY THE FIRST INVESTIGATIONS ON IBD FAMILIES AND TWINS, THE GENETIC AND EPIGENETIC STUDIES HAVE PRODUCED AN UNPRECEDENTED AMOUNT OF INFORMATION IN COMPARISON WITH OTHER IMMUNE-MEDIATED OR COMPLEX DISEASES. NEW INFLAMMATORY PATHWAYS AND POSSIBLE MECHANISMS OF ACTION HAVE BEEN DISCLOSED, POTENTIALLY LEADING TO NEW-TARGETED THERAPY. HOWEVER, THE IDENTIFICATION OF GENETIC MARKERS DUE TO THE GREAT DISEASE HETEROGENEITY AND THE OVERWHELMING CONTRIBUTION OF ENVIRONMENTAL RISK FACTORS HAS NOT MODIFIED YET THE DISEASE MANAGEMENT. THE POSSIBILITY FOR THE FUTURE OF A BETTER PREDICTION OF DISEASE COURSE, RESPONSE TO THERAPY AND THERAPY-RELATED ADVERSE EVENTS MAY ALLOW A MORE EFFICIENT AND PERSONALIZED STRATEGY. THIS REVIEW WILL FOCUS ON MORE RECENT DISCOVERIES THAT MAY POTENTIALLY BE OF RELEVANCE IN DAILY CLINICAL PRACTICE. 2020 12 3404 37 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 13 5643 32 SEX AND AUTOIMMUNITY: PROPOSED MECHANISMS OF DISEASE ONSET AND SEVERITY. CHRONIC AUTOIMMUNE DISEASES AFFECT 5-10% OF THE POPULATION WORLDWIDE AND ARE LARGELY PREDOMINANT IN WOMEN. SEX HORMONE CHANGES HAVE BEEN WIDELY INVESTIGATED BASED ON CHANGES IN THE CLINICAL PHENOTYPES OBSERVED DURING PREGNANCY AND MENOPAUSE. IT IS KNOWN THAT FEMALES WITH AUTOIMMUNE DISEASES MANIFEST A HIGHER RATE OF CIRCULATING LEUKOCYTES WITH A SINGLE X CHROMOSOME, AND THERE HAVE BEEN SEVERAL REPORTS ON THE ROLE OF X CHROMOSOME GENE DOSAGE THROUGH INACTIVATION OR DUPLICATION IN AUTOIMMUNITY. HOWEVER, IT IS ALSO IMPORTANT NOT TO OVERLOOK MEN WITH AUTOIMMUNE DISEASES, WHO MIGHT MANIFEST A MORE FREQUENT LOSS OF THE Y CHROMOSOME IN CIRCULATING LEUKOCYTES. AREAS COVERED: IN THE PRESENT REVIEW, WE WILL DISCUSS THE CURRENT EVIDENCE SUPPORTING THE MECHANISMS OF FEMALE PREDOMINANCE IN RHEUMATIC DISEASES, BY DISCUSSING THE ROLE OF REPRODUCTIVE HISTORY, SEX HORMONES AND ABNORMALITIES RELATED TO THEM, CLINICAL DIFFERENCES BETWEEN MALE AND FEMALE PATIENTS, AND EPIGENETIC CHANGES THAT HAVE BEEN EVALUATED THROUGH TWIN STUDIES ON GENETIC AND ENVIRONMENTAL CHANGES IN RHEUMATIC PATIENTS. EXPERT OPINION: THE INFLUENCE OF SEX HORMONES AND CHROMOSOMES ON THE FUNCTION OF THE INNATE AND ADAPTIVE IMMUNE SYSTEMS NEEDS TO BE CLARIFIED, TO BETTER UNDERSTAND THE RISK OF AUTOIMMUNE DISEASES, EARLY DIAGNOSTIC TOOLS, AND THERAPEUTIC RESPONSE. 2019 14 724 35 CAN GENETICS GUIDE EXERCISE PRESCRIPTIONS IN OSTEOARTHRITIS? OSTEOARTHRITIS (OA) IS THE MOST COMMON FORM OF ARTHRITIS AND HAS A MULTIFACTORIAL ETIOLOGY. CURRENT MANAGEMENT FOR OA FOCUSES ON MINIMIZING PAIN AND FUNCTIONAL LOSS, TYPICALLY INVOLVING PHARMACOLOGICAL, PHYSICAL, PSYCHOSOCIAL, AND MIND-BODY INTERVENTIONS. HOWEVER, THERE REMAIN CHALLENGES IN DETERMINING WHICH PATIENTS WILL BENEFIT MOST FROM WHICH INTERVENTIONS. ALTHOUGH EXERCISE-BASED INTERVENTIONS ARE RECOMMENDED AS FIRST-LINE TREATMENTS AND ARE KNOWN TO BE BENEFICIAL FOR MANAGING BOTH THE DISEASE AND ILLNESS OF OA, THE OPTIMAL EXERCISE "PRESCRIPTION" IS UNKNOWN, DUE IN PART TO OUR LIMITED UNDERSTANDING OF THE PRECISE MECHANISMS UNDERLYING ITS ACTION. HERE WE PRESENT OUR PERSPECTIVE ON THE POTENTIAL ROLE OF GENETICS IN GUIDING EXERCISE PRESCRIPTION FOR PERSONS WITH OA. WE DESCRIBE KEY PUBLICATIONS IN THE AREAS OF EXERCISE AND OA, GENETICS AND OA, AND EXERCISE AND GENETICS, AND POINT TO A PAUCITY OF KNOWLEDGE AT THE INTERSECTION OF EXERCISE, GENETICS, AND OA. WE SUGGEST THERE IS EMERGING EVIDENCE TO SUPPORT THE USE OF GENETICS AND EPIGENETICS TO EXPLAIN THE BENEFICIAL EFFECTS OF EXERCISE FOR OA. WE IDENTIFY MISSING LINKS IN THE EXISTING RESEARCH RELATING TO EXERCISE, GENETICS, AND OA, AND HIGHLIGHT EPIGENETICS AS A PROMISING MECHANISM THROUGH WHICH ENVIRONMENTAL EXPOSURES SUCH AS EXERCISE MAY IMPACT OA OUTCOMES. WE ANTICIPATE FUTURE STUDIES WILL IMPROVE OUR UNDERSTANDING OF HOW GENETIC AND EPIGENETIC FACTORS MEDIATE EXERCISE-BASED INTERVENTIONS TO SUPPORT IMPLEMENTATION AND ULTIMATELY IMPROVE OA PATIENT CARE. 2022 15 738 33 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 4325 34 MICRORNAS IN THE EVALUATION AND POTENTIAL TREATMENT OF LIVER DISEASES. ACUTE AND CHRONIC LIVER DISEASE CONTINUE TO RESULT IN SIGNIFICANT MORBIDITY AND MORTALITY OF PATIENTS, ALONG WITH INCREASING BURDEN ON THEIR FAMILIES, SOCIETY AND THE HEALTH CARE SYSTEM. THIS IN PART IS DUE TO INCREASED INCIDENCE OF LIVER DISEASE ASSOCIATED FACTORS SUCH AS METABOLIC SYNDROME; IMPROVED SURVIVAL OF PATIENTS WITH CHRONIC PREDISPOSING CONDITIONS SUCH AS HIV; AS WELL AS ADVANCES IN THE FIELD OF TRANSPLANTATION AND ASSOCIATED CARE LEADING TO IMPROVED SURVIVAL. THE FACT THAT ONE DISEASE CAN RESULT IN DIFFERENT MANIFESTATIONS AND OUTCOMES HIGHLIGHTS THE NEED FOR IMPROVED UNDERSTANDING OF NOT JUST GENETIC PHENOMENON PREDISPOSING TO A CONDITION, BUT ADDITIONALLY THE ROLE OF EPIGENETIC AND ENVIRONMENTAL FACTORS LEADING TO THE PHENOTYPE OF THE DISEASE. IT IS NOT SURPRISING THAT PROVIDERS CONTINUE TO FACE DAILY CHALLENGES PERTAINING TO DIAGNOSTIC ACCURACY, PROGNOSTICATION OF DISEASE SEVERITY, PROGRESSION, AND RESPONSE TO THERAPIES. A NUMBER OF THESE CHALLENGES CAN BE ADDRESSED BY INCORPORATING A PERSONALIZED APPROACH OF MANAGEMENT TO THE CURRENT PARADIGM OF CARE. RECENT ADVANCES IN THE FIELDS OF MOLECULAR BIOLOGY AND GENETICS HAVE PAVED THE WAY TO MORE ACCURATE, INDIVIDUALIZED AND PRECISE APPROACH TO CARING FOR LIVER DISEASE. THE STUDY OF MICRORNAS AND THEIR ROLE IN BOTH HEALTHY AND DISEASED LIVERS IS ONE EXAMPLE OF SUCH ADVANCES. AS THESE SMALL, NON-CODING RNAS WORK ON FINE-TUNING OF CELLULAR ACTIVITIES AND ORGAN FUNCTION IN A DYNAMIC AND PRECISE FASHION, THEY PROVIDE US A GOLDEN OPPORTUNITY TO ADVANCE THE FIELD OF HEPATOLOGY. THE STUDY OF MICRORNAS IN LIVER DISEASE PROMISES TREMENDOUS IMPROVEMENT IN HEPATOLOGY AND IS LIKELY TO LAY THE FOUNDATION TOWARDS A PERSONALIZED APPROACH IN LIVER DISEASE. 2016 17 6791 27 [DOES THE NUMBER OF PATIENTS WITH AUTOIMMUNE DISORDERS AND THE FREQUENCY OF AUTOIMMUNE DISEASES INCREASE?]. AUTOIMMUNE DISEASES GENERALLY BELONG TO THE RARE DISEASES, HOWEVER, SOME OF THEM ARE FREQUENT IN THE POPULATION. IN THE PRESENT WORK THE AUTHORS ANALYSE WHETHER CAN ANY INCREASE BE OBSERVED IN THE NUMBER OF PATIENTS SUFFERING FROM AUTOIMMUNE DISEASES AND WHETHER DO THE FREQUENCY OF CERTAIN AUTOIMMUNE DISORDERS INCREASE. DUE MAINLY TO EPIGENETIC FACTORS THE INCIDENCE OF AUTOIMMUNE DISEASES ARE INCREASING, THEREFORE THERE ARE MORE PATIENTS RECOGNISED WITH PARTICULAR DISORDERS. ON THE OTHER HAND THE INCIDENCE IS INCREASED BY IMPROVING DIAGNOSTIC POSSIBILITIES, BY THE USE OF MORE SPECIFIC AND SENSITIVE CLASSIFICATION CRITERIA AND MORE SOPHISTICATED LABORATORY TESTS, RESULTED IN THE RECOGNITION OF MILDER AND ATYPICAL DISEASE VARIANTS AS WELL. THE PREVALENCE IS ALSO INCREASING IN CONSEQUENCE OF NOVEL IMMUNE SUPPRESSIVE THERAPEUTIC POSSIBILITIES AND THE CONSEQUENT IMPROVEMENT OF SURVIVAL IN THE MOST OF THESE DISEASES. BESIDES, MORE AND MORE DISEASES HAVE BEEN REVEALED TO HAVE AUTOIMMUNE BACKGROUND, AND LOT OF NEW AUTOIMMUNE SYNDROMES, DISEASES HAVE BEEN CHARACTERISED RECENTLY. THIS INCREASES THE NUMBER OF THE KNOWN AUTOIMMUNE RHEUMATIC DISORDERS WITH A CONSEQUENT INCREASE IN THE NUMBER OF AUTOIMMUNE PATIENTS. ASSIGNED TO THE INCREASING NUMBER OF VARIABLE CHRONIC AUTOIMMUNE DISORDERS, AND THE INCREASING NUMBER OF DISABLED PATIENTS WITH SUCH DISEASES INCREASING MEDICAL AND SOCIAL ATTENTION HAS TO BE FOCUSED ON. 2007 18 1248 31 CURRENT EVIDENCE FOR BIOLOGICAL BIOMARKERS AND MECHANISMS UNDERLYING ACUTE TO CHRONIC PAIN TRANSITION ACROSS THE PEDIATRIC AGE SPECTRUM. CHRONIC PAIN IS HIGHLY PREVALENT IN THE PEDIATRIC POPULATION. MANY FACTORS ARE INVOLVED IN THE TRANSITION FROM ACUTE TO CHRONIC PAIN. CURRENTLY, THERE ARE CONCEPTUAL MODELS PROPOSED, BUT THEY LACK A MECHANISTICALLY SOUND INTEGRATED THEORY CONSIDERING THE STAGES OF CHILD DEVELOPMENT. OBJECTIVE BIOMARKERS ARE CRITICALLY NEEDED FOR THE DIAGNOSIS, RISK STRATIFICATION, AND PROGNOSIS OF THE PATHOLOGICAL STAGES OF PAIN CHRONIFICATION. IN THIS ARTICLE, WE SUMMARIZE THE CURRENT EVIDENCE ON MECHANISMS AND BIOMARKERS OF ACUTE TO CHRONIC PAIN TRANSITIONS IN INFANTS AND CHILDREN THROUGH THE DEVELOPMENTAL LENS. THE GOAL IS TO IDENTIFY GAPS AND OUTLINE FUTURE DIRECTIONS FOR BASIC AND CLINICAL RESEARCH TOWARD A DEVELOPMENTALLY INFORMED THEORY OF PAIN CHRONIFICATION IN THE PEDIATRIC POPULATION. AT THE OUTSET, THE IMPORTANCE OF OBJECTIVE BIOMARKERS FOR CHRONIFICATION OF PAIN IN CHILDREN IS OUTLINED, FOLLOWED BY A SUMMARY OF THE CURRENT EVIDENCE ON THE MECHANISMS OF ACUTE TO CHRONIC PAIN TRANSITION IN ADULTS, IN ORDER TO CONTRAST WITH THE DEVELOPMENTAL MECHANISMS OF PAIN CHRONIFICATION IN THE PEDIATRIC POPULATION. EVIDENCE IS PRESENTED TO SHOW THAT CHRONIC PAIN MAY HAVE ITS ORIGIN FROM INSULTS EARLY IN LIFE, WHICH PRIME THE CHILD FOR THE DEVELOPMENT OF CHRONIC PAIN IN LATER LIFE. FURTHERMORE, AVAILABLE GENETIC, EPIGENETIC, PSYCHOPHYSICAL, ELECTROPHYSIOLOGICAL, NEUROIMAGING, NEUROIMMUNE, AND SEX MECHANISMS ARE DESCRIBED IN INFANTS AND OLDER CHILDREN. IN CONCLUSION, FUTURE DIRECTIONS ARE DISCUSSED WITH A FOCUS ON RESEARCH GAPS, TRANSLATIONAL AND CLINICAL IMPLICATIONS. UTILIZATION OF DEVELOPMENTAL MECHANISMS FRAMEWORK TO INFORM CLINICAL DECISION-MAKING AND STRATEGIES FOR PREVENTION AND MANAGEMENT OF ACUTE TO CHRONIC PAIN TRANSITIONS IN CHILDREN, IS HIGHLIGHTED. 2023 19 2651 33 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 20 2447 30 EPIGENETIC STUDIES IN ALZHEIMER'S DISEASE: CURRENT FINDINGS, CAVEATS, AND CONSIDERATIONS FOR FUTURE STUDIES. ALZHEIMER'S DISEASE (AD) IS A SPORADIC, CHRONIC NEURODEGENERATIVE DISEASE, USUALLY OCCURRING LATE IN LIFE. THE LAST DECADE HAS WITNESSED TREMENDOUS ADVANCES IN OUR UNDERSTANDING ABOUT THE GENETIC BASIS OF AD, BUT A LARGE AMOUNT OF THE VARIANCE IN DISEASE RISK REMAINS TO BE EXPLAINED. EPIGENETIC MECHANISMS, WHICH DEVELOPMENTALLY REGULATE GENE EXPRESSION VIA MODIFICATIONS TO DNA, HISTONE PROTEINS, AND CHROMATIN, HAVE BEEN HYPOTHESIZED TO PLAY A ROLE IN OTHER COMPLEX NEUROBIOLOGICAL DISEASES, AND STUDIES TO IDENTIFY GENOME-WIDE EPIGENETIC CHANGES IN AD ARE CURRENTLY UNDER WAY. HOWEVER, THE SIMPLE BRUTE-FORCE APPROACH THAT HAS BEEN SUCCESSFULLY EMPLOYED IN GENOME-WIDE ASSOCIATION STUDIES IS UNLIKELY TO BE SUCCESSFUL IN EPIGENOME-WIDE ASSOCIATION STUDIES OF NEURODEGENERATION. A MORE ACADEMIC APPROACH TO UNDERSTANDING THE ROLE OF EPIGENETIC VARIATION IN AD IS REQUIRED, WITH CAREFUL CONSIDERATION OF STUDY DESIGN, METHODOLOGICAL APPROACHES, TISSUE-SPECIFICITY, AND CAUSAL INFERENCE. IN THIS ARTICLE, WE REVIEW THE EMPIRICAL LITERATURE SUPPORTING A ROLE FOR EPIGENETIC PROCESSES IN AD, AND DISCUSS IMPORTANT CONSIDERATIONS AND FUTURE DIRECTIONS FOR THIS NEW AND EMERGING FIELD OF RESEARCH. 2013