1 5232 148 PROBLEMS IN ASSESSMENT OF RISKS FROM EXPOSURES TO MICROWAVES OF MOBILE COMMUNICATION. SINCE PIONEERING INVESTIGATIONS PUBLISHED IN THE BEGINNING OF 1970TH, VARIOUS BIOLOGICAL RESPONSES TO NON-THERMAL (NT) MICROWAVES (MW), INCLUDING ADVERSE HEALTH EFFECTS, HAVE BEEN DESCRIBED BY MANY RESEARCH GROUPS ALL OVER THE WORLD. THERE IS STRONG EVIDENCE THAT THE NT MW BIOLOGICAL EFFECTS DEPEND ON SEVERAL PHYSICAL PARAMETERS AND BIOLOGICAL VARIABLES, WHICH MUST BE CONTROLLED IN REPLICATION STUDIES. APART FROM THE FUNDAMENTAL IMPORTANCE, THE DEVELOPMENT OF COMPREHENSIVE MECHANISMS FOR THE NT MW EFFECTS IS SOCIALLY IMPORTANT. THE EFFECTS OF MW OF MOBILE COMMUNICATIONS ARE OF MAJOR CONCERN BECAUSE OF THE INCREASED EXPOSURE IN MANY COUNTRIES. IT HAS BEEN SHOWN THAT ADVERSE EFFECTS OF NT MW FROM GSM/UMTS MOBILE PHONES ON HUMAN LYMPHOCYTES FROM HEALTHY AND HYPERSENSITIVE TO EMF PERSONS DEPEND ON CARRIER FREQUENCY AND MODULATION. FURTHER INVESTIGATIONS WITH HUMAN PRIMARY CELLS, ANIMALS AND VOLUNTEERS ARE NEEDED TO ELUCIDATE POSSIBLE ADVERSE EFFECTS OF MW SIGNALS THAT ARE USED IN WIRELESS COMMUNICATION. IDENTIFICATION OF THOSE TYPES AND FREQUENCY CHANNELS/BANDS FOR MOBILE COMMUNICATION, WHICH DO NOT AFFECT HUMAN CELLS, IS URGENTLY NEEDED AS THE HIGH PRIORITY TASK FOR THE DEVELOPMENT OF SAFE MOBILE COMMUNICATION. NUMEROUS DATA ON THE NT MW EFFECTS CLEARLY INDICATE THAT THE SAR-CONCEPT ALONE CANNOT UNDERLIE THE SAFETY GUIDELINES FOR CHRONIC EXPOSURES TO MW FROM MOBILE COMMUNICATION AND OTHER APPROACHES ARE NEEDED. HOWEVER, THERE IS NOT ENOUGH RESEARCH INFORMATION TO SET EXPOSURE MW STANDARDS. VARIOUS GENETIC AND EPIGENETIC EFFECTS OF SIGNALS USED IN MOBILE COMMUNICATION SHOULD BE STUDIED. IT HAS BEEN SHOWN THAT NT MW AFFECT CELLS OF VARIOUS TYPES INCLUDING STEM CELLS AND REPRODUCTIVE ORGANS. STEM CELLS REPRESENT ESPECIALLY IMPORTANT CELLULAR MODEL BECAUSE RECENT DATA SUGGEST THAT DIFFERENT CANCER TYPES, INCLUDING LEUKEMIA, HAVE A FUNDAMENTALLY COMMON BASIS THAT IS GROUNDED ON EPIGENETIC CHANGES IN STEM CELLS. 2007 2 6570 28 TRANSPOSABLE ELEMENTS AND THEIR POTENTIAL ROLE IN COMPLEX LUNG DISORDER. TRANSPOSABLE ELEMENTS (TES) ARE A CLASS OF MOBILE GENETIC ELEMENTS (MGES) THAT WERE LONG REGARDED AS JUNK DNA, WHICH MAKE UP APPROXIMATELY 45% OF THE GENOME. ALTHOUGH MOST OF THESE ELEMENTS ARE RENDERED INACTIVE BY MUTATIONS AND OTHER GENE SILENCING MECHANISMS, TES SUCH AS LONG INTERSPERSED NUCLEAR ELEMENTS (LINES) ARE STILL ACTIVE AND TRANSLOCATE WITHIN THE GENOME. DURING TRANSPOSITION, THEY MAY CREATE LESIONS IN THE GENOME, THEREBY ACTING AS EPIGENETIC MODIFIERS. APPROXIMATELY 65 DISEASE-CAUSING LINE INSERTION EVENTS HAVE BEEN REPORTED THUS FAR; HOWEVER, ANY POSSIBLE ROLE OF TES IN COMPLEX DISORDERS IS NOT WELL ESTABLISHED. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS ONE SUCH COMPLEX DISEASE THAT IS PRIMARILY CAUSED BY CIGARETTE SMOKING. ALTHOUGH THE EXACT MOLECULAR MECHANISM UNDERLYING COPD REMAINS UNCLEAR, OXIDATIVE STRESS IS THOUGHT TO BE THE MAIN FACTOR IN THE PATHOGENESIS OF COPD. IN THIS REVIEW, WE EXPLORE THE POTENTIAL ROLE OF OXIDATIVE STRESS IN EPIGENETIC ACTIVATION OF TES SUCH AS LINES AND THE SUBSEQUENT CASCADE OF MOLECULAR DAMAGE. RECENT ADVANCEMENTS IN SEQUENCING AND COMPUTATION HAVE EASED THE IDENTIFICATION OF MOBILE ELEMENTS. THEREFORE, A COMPARATIVE STUDY ON THE ACTIVITY OF THESE ELEMENTS AND MARKERS FOR GENOME INSTABILITY WOULD GIVE MORE INSIGHT ON THE RELATIONSHIP BETWEEN MGES AND COMPLEX DISORDER SUCH AS COPD. 2013 3 3418 30 HUMAN HEALTH CONSEQUENCES OF ENVIRONMENTALLY-MODULATED GENE EXPRESSION: POTENTIAL ROLES OF ELF-EMF INDUCED EPIGENETIC VERSUS MUTAGENIC MECHANISMS OF DISEASE. IN ORDER TO DETERMINE IF THERE MIGHT BE BIOLOGICAL AND HEALTH CONSEQUENCES AFTER EXPOSURES TO EXTREMELY-LOW FREQUENCY ELECTROMAGNETIC FIELDS (ELF-EMF), EITHER EXPERIMENTALLY OR EPIDEMIOLOGICALLY, MECHANISTIC UNDERSTANDING OF THE POTENTIAL MEANS BY WHICH ANY ENVIRONMENTAL AGENT CAN AFFECT CELLS IN A MULTICELLULAR ORGANISM HAS TO BE REVIEWED. THE GOAL OF THIS LIMITED REVIEW IS TO DEMONSTRATE THAT, WHILE THE PREVAILING PARADIGM OF THE ENVIRONMENTALLY-INDUCED ACUTE AND CHRONIC DISEASES INVOLVES EITHER CELL KILLING (CYTOTOXICITY) OR GENE/CHROMOSOME MUTATIONS (GENOTOXICITY), ALTERATION OF THE EXPRESSION OF GENETIC INFORMATION AT THE TRANSCRIPTIONAL (TURNING GENES "ON" OR "OFF"), TRANSLATIONAL (STABILIZING OR DE-STABILIZING THE GENETIC MESSAGE), OR POSTTRANSLATIONAL (ALTERING THE GENE PRODUCT OR PROTEIN) LEVELS HAS THE POTENTIAL TO CONTRIBUTE TO VARIOUS DISEASES. THIS LATTER MECHANISM, "EPIGENETIC" TOXICITY, UNLIKE THE FORMER TWO WHICH ARE IRREVERSIBLE, IS CHARACTERIZED BY THRESHOLD-LIKE ACTION, MULTIPLE BIOCHEMICAL PATHWAYS AND CHRONIC, REGULAR EXPOSURES TO BE EFFECTIVE. ULTIMATELY, EPIGENETIC TOXICANTS AFFECT ONE OF FOUR POTENTIAL CELL STATES, NAMELY ALTERATION OF CELL PROLIFERATION, CELL DIFFERENTIATION, PROGRAMMED CELL DEATH (APOPTOSIS) OR ADAPTIVE RESPONSES OF DIFFERENTIATED CELLS. 2000 4 2901 40 GENDER DIFFERENCES IN GERM-CELL MUTAGENESIS AND GENETIC RISK. CURRENT INTERNATIONAL CLASSIFICATION SYSTEMS FOR CHEMICAL MUTAGENS ARE HAZARD-BASED RATHER THAN AIMED AT ASSESSING RISKS QUANTITATIVELY. IN THE PAST, GERM-CELL TESTS HAVE BEEN MAINLY PERFORMED WITH A LIMITED NUMBER OF SOMATIC CELL MUTAGENS, AND RARELY UNDER CONDITIONS AIMED AT COMPARING GENDER-SPECIFIC DIFFERENCES IN SUSCEPTIBILITY TO MUTAGEN EXPOSURES. THERE ARE PROFOUND DIFFERENCES IN THE GENETIC CONSTITUTION, AND IN HORMONAL, STRUCTURAL, AND FUNCTIONAL ASPECTS OF DIFFERENTIATION AND CONTROL OF GAMETOGENESIS BETWEEN THE SEXES. A CRITICAL REVIEW OF THE LITERATURE SUGGESTS THAT THESE DIFFERENCES MAY HAVE A PROFOUND IMPACT ON THE RELATIVE SUSCEPTIBILITY, STAGE OF HIGHEST SENSITIVITY AND THE RELATIVE RISK FOR THE GENESIS OF GENE MUTATION, AS WELL AS STRUCTURAL AND NUMERICAL CHROMOSOMAL ABERRATIONS IN MALE AND FEMALE GERM CELLS. TRANSMISSION OF GERM-CELL MUTATIONS TO THE OFFSPRING MAY ALSO ENCOUNTER GENDER-SPECIFIC INFLUENCES. GENDER DIFFERENCES IN SUSCEPTIBILITY TO CHEMICALLY DERIVED ALTERATIONS IN IMPRINTING PATTERNS MAY POSE A THREAT FOR THE HEALTH OF THE OFFSPRING AND MAY ALSO BE TRANSMITTED TO FUTURE GENERATIONS. RECENT REPORTS ON DIFFERENT GENETIC EFFECTS FROM HIGH ACUTE AND FROM CHRONIC LOW-DOSE EXPOSURES CHALLENGE THE VALIDITY OF CONCLUSIONS DRAWN FROM STANDARD METHODS OF MUTAGENICITY TESTING. IN CONCLUSION, RESEARCH IS URGENTLY NEEDED TO IDENTIFY GENETIC HAZARDS FOR A LARGER RANGE OF CHEMICAL COMPOUNDS, INCLUDING THOSE SUSPECTED TO DISTURB PROPER CHROMOSOME SEGREGATION. ALTERATIONS IN EPIGENETIC PROGRAMMING AND THEIR HEALTH CONSEQUENCES WILL HAVE TO BE INVESTIGATED. MORE ATTENTION SHOULD BE PAID TO GENDER-SPECIFIC GENETIC EFFECTS. FINALLY, THE DATABASE FOR GERM-CELL MUTAGENS SHOULD BE ENLARGED USING MOLECULAR METHODOLOGIES, AND GENETIC EPIDEMIOLOGY STUDIES SHOULD BE PERFORMED WITH THESE TECHNIQUES TO VERIFY HUMAN GENETIC RISK. 2007 5 761 34 CATEGORIZING THE CHARACTERISTICS OF HUMAN CARCINOGENS: A NEED FOR SPECIFICITY. THE INTERNATIONAL AGENCY FOR RESEARCH ON CANCER (IARC) HAS RECENTLY PROPOSED EMPLOYING "TEN KEY CHARACTERISTICS OF HUMAN CARCINOGENS" (TKCS) TO DETERMINE THE POTENTIAL OF AGENTS FOR HARMFUL EFFECTS. THE TKCS SEEM LIKELY TO CONFUSE THE UNSATISFACTORY CORRELATION FROM TESTING REGIMES THAT HAVE IGNORED THE DIFFERENCES EVIDENT WHEN CELLULAR CHANGES ARE COMPARED IN SHORT AND LONG-LIVED SPECIES, WITH THEIR VERY DIFFERENT STEM CELL AND SOMATIC CELL PHYLOGENIES. THE PROPOSED CHARACTERISTICS ARE SO BROAD THAT THEIR USE WILL LEAD TO AN INCREASE IN THE CURRENT UNACCEPTABLY HIGH RATE OF FALSE POSITIVES. IT COULD BE AN INFORMATIVE EXPERIMENT TO TAKE WELL-ESTABLISHED APPROVED THERAPEUTICS WITH WELL-KNOWN HUMAN SAFETY PROFILES AND TEST THEM AGAINST THIS NEW TKC PARADIGM. CANCERS ARE INITIATED AND DRIVEN BY HERITABLE AND TRANSIENT CHANGES IN GENE EXPRESSION, EXPAND CLONALLY, AND PROGRESS VIA ADDITIONAL ASSOCIATED ACQUIRED MUTATIONS AND EPIGENETIC ALTERATIONS THAT PROVIDE CELLS WITH AN EVOLUTIONARY ADVANTAGE. THE GENOTOXICITY TESTING PROTOCOLS CURRENTLY EMPLOYED AND REQUIRED BY REGULATION, EMPHASIZE TESTING FOR THE MUTATIONAL POTENTIAL OF THE TEST AGENT. TWO-YEAR, CHRONIC RODENT CANCER BIOASSAYS ARE INTENDED TO TEST FOR THE ENTIRE SPECTRUM OF CARCINOGENIC TRANSFORMATION. THE USE OF CYTOTOXIC DOSES CAUSING INCREASED, SUSTAINED CELL PROLIFERATION THAT FACILITATES ACCUMULATED GENETIC DAMAGE LEADS TO A HIGH FALSE-POSITIVE RATE OF TUMOR INDUCTION. CURRENT CANCER HAZARD ASSESSMENT PROTOCOLS AND WEIGHT-OF-THE-EVIDENCE ANALYSIS OF AGENT-SPECIFIC CANCER RISK ALIGN POORLY WITH THE PATHOGENESIS OF HUMAN CARCINOMA AND SO NEED MODERNIZATION AND IMPROVEMENT IN WAYS SUGGESTED HERE. 2021 6 705 31 BUILDING RISK-ON-A-CHIP MODELS TO IMPROVE BREAST CANCER RISK ASSESSMENT AND PREVENTION. PREVENTIVE ACTIONS FOR CHRONIC DISEASES HOLD THE PROMISE OF IMPROVING LIVES AND REDUCING HEALTHCARE COSTS. FOR SEVERAL DISEASES, INCLUDING BREAST CANCER, MULTIPLE RISK AND PROTECTIVE FACTORS HAVE BEEN IDENTIFIED BY EPIDEMIOLOGISTS. THE IMPACT OF MOST OF THESE FACTORS HAS YET TO BE FULLY UNDERSTOOD AT THE ORGANISM, TISSUE, CELLULAR AND MOLECULAR LEVELS. IMPORTANTLY, COMBINATIONS OF EXTERNAL AND INTERNAL RISK AND PROTECTIVE FACTORS INVOLVE COOPERATIVITY THUS, SYNERGIZING OR ANTAGONIZING DISEASE ONSET. MODELS ARE NEEDED TO MECHANISTICALLY DECIPHER CANCER RISKS UNDER DEFINED CELLULAR AND MICROENVIRONMENTAL CONDITIONS. HERE, WE BRIEFLY REVIEW BREAST CANCER RISK MODELS BASED ON 3D CELL CULTURE AND PROPOSE TO IMPROVE RISK MODELING WITH LAB-ON-A-CHIP APPROACHES. WE SUGGEST EPITHELIAL TISSUE POLARITY, DNA REPAIR AND EPIGENETIC PROFILES AS ENDPOINTS IN RISK ASSESSMENT MODELS AND DISCUSS THE DEVELOPMENT OF 'RISKS-ON-CHIPS' INTEGRATING BIOSENSORS OF THESE ENDPOINTS AND OF GENERAL TISSUE HOMEOSTASIS. RISKS-ON-CHIPS WILL HELP IDENTIFY BIOMARKERS OF RISK, SERVE AS SCREENING PLATFORMS FOR CANCER PREVENTIVE AGENTS, AND PROVIDE A BETTER UNDERSTANDING OF RISK MECHANISMS, HENCE RESULTING IN NOVEL DEVELOPMENTS IN DISEASE PREVENTION. 2013 7 2136 38 EPIGENETIC INFLUENCES IN THE OBESITY/COLORECTAL CANCER AXIS: A NOVEL THERAGNOSTIC AVENUE. THE WORLD HEALTH ORGANIZATION (WHO) CONSIDERS THAT OBESITY HAS REACHED PROPORTIONS OF PANDEMIC. EXPERTS ALSO INSIST ON THE IMPORTANCE OF CONSIDERING OBESITY AS A CHRONIC DISEASE AND ONE OF THE MAIN CONTRIBUTORS TO THE WORLDWIDE BURDEN OF OTHER NONTRANSMISSIBLE CHRONIC DISEASES, WHICH HAVE A GREAT IMPACT ON HEALTH, LIFESTYLE, AND ECONOMIC COST. ONE OF THE MOST CURRENT CHALLENGES OF BIOMEDICAL SCIENCE FACES IS TO UNDERSTAND THE ORIGIN OF THE CHRONIC NONTRANSMISSIBLE DISEASES, SUCH AS OBESITY AND CANCER. THERE IS A LARGE EVIDENCE, BOTH IN EPIDEMIOLOGICAL STUDIES IN HUMANS AND IN ANIMAL MODELS, OF THE ASSOCIATION BETWEEN OBESITY AND AN INCREASED RISK OF CANCER INCIDENCE. IN THE LAST YEARS, THE INITIAL DISCOVERY OF EPIGENETIC MECHANISMS REPRESENTS THE MOST RELEVANT FINDING TO EXPLAIN HOW THE GENOME INTERACTS WITH ENVIRONMENTAL FACTORS AND THE RIPPLE EFFECTS ON DISEASE PATHOGENESES. SINCE THEN, ALL EPIGENETIC PROCESS HAS BEEN INVESTIGATED BY THE SCIENTIFIC COMMUNITIES FOR NEARLY TWO DECADES TO DETERMINE WHICH COMPONENTS ARE INVOLVED IN THIS PROCESS. DNA/RNA METHYLATION AND MIRNA ARE CLASSIFIED AS TWO OF THE MOST IMPORTANT REPRESENTATIVE CLASSES OF SUCH EPIGENETIC MECHANISMS AND DYSREGULATED ACTIVITY OF SUCH MECHANISM CAN CERTAINLY CONTRIBUTE TO DISEASE PATHOGENESIS AND/OR PROGRESSION ESPECIALLY IN TUMORS. THIS REVIEW ARTICLE SERVES TO HIGHLIGHT THE IMPACT OF DNA/RNA METHYLATION AND MIRNA-BASED EPIGENETIC MECHANISM ACTIVITIES IN THE INTERPLAY BETWEEN OBESITY AND THE DEVELOPMENT AND CLINICAL SIGNIFICANCE OF COLORECTAL CANCER. 2019 8 4399 40 MODULATION OF GENOMIC AND POSTGENOMIC ALTERATIONS IN NONCANCER DISEASES AND CRITICAL PERIODS OF LIFE. GENOMIC AND POSTGENOMIC CHANGES ARE EXTENSIVELY INVESTIGATED IN CANCER RESEARCH. SIMILAR ALTERATIONS, AFFECTING GENOME, TRANSCRIPTOME, MIRNOME AND/OR PROTEOME END-POINTS, HAVE BEEN DETECTED IN A VARIETY OF OTHER CHRONIC DEGENERATIVE DISEASES, SUCH AS ATHEROSCLEROSIS, DEGENERATIVE HEART DISEASES, CHRONIC OBSTRUCTIVE PULMONARY DISEASES, NEUROLOGICAL DISORDERS, EYE DISEASES, DIABETES, METABOLIC SYNDROME, SKIN AGEING AND ALOPECIA. NO GENERALIZATION CAN BE MADE DUE TO THE MYRIAD OF DIVERSE CLINICAL ENTITIES CLASSIFIED AS CHRONIC DEGENERATIVE DISEASES. MOREOVER, THE DETECTION OF MOLECULAR CHANGES DOES NOT AUTOMATICALLY IMPLY THEIR CAUSAL ROLE. NEVERTHELESS, COMMON MECHANISMS, SUCH AS DNA DAMAGE, EPIGENETIC ALTERATIONS, OXIDATIVE STRESS, AND CHRONIC INFLAMMATION, IN ADDITION TO GENETIC PREDISPOSITION, ARE OFTEN INVOLVED IN NONCANCER DISEASES. WE DEBATE HERE IN MORE DETAIL THE SUBJECTS OF CARDIOVASCULAR DISEASES AND OF SKIN DISEASES. MOREOVER, WE DISCUSS OUR EXPERIMENTAL STUDIES SUGGESTING THAT GENOMIC AND POSTGENOMIC CHANGES DO ALSO OCCUR DURING CRITICAL PERIODS OF LIFE, INCLUDING THE PRENATAL LIFE, THE PERINATAL PERIOD, AND AGEING. IN ADDITION, WE COMMENT ON THE FINDING THAT STEM-DERIVED CELLS ARE MORE SUSCEPTIBLE TO MOLECULAR DAMAGE THAN MORE DIFFERENTIATED CELLS. ALL THESE DATA ARE VIEWED IN THE PERSPECTIVE OF PREVENTIVE MEDICINE. IN FACT, THERE IS EVIDENCE THAT THE GENOMIC AND POSTGENOMIC ALTERATIONS OCCURRING NOT ONLY IN SEVERAL PATHOLOGICAL CONDITIONS BUT ALSO IN PARAPHYSIOLOGICAL SITUATIONS THAT AFFECT CRITICAL PERIODS OF LIFE CAN BE MODULATED BY MEANS OF DIETARY AND PHARMACOLOGICAL AGENTS. THE DISCOVERY THAT CHEMOPREVENTIVE AGENTS ARE ALSO ABLE TO ATTENUATE NUCLEOTIDE DAMAGE IN STEM-DERIVED CELLS WARRANTS FURTHER STUDIES IN VIEW OF POSSIBLE CLINICAL APPLICATIONS. 2009 9 1340 34 DESIGNING SAFER DRUGS: (Q)SAR-BASED IDENTIFICATION OF MUTAGENS AND CARCINOGENS. MUTAGENICITY AND CARCINOGENICITY ARE CHRONIC EFFECTS OF PRIMARY CONCERN FOR HUMAN HEALTH. A UNIFYING APPROACH TO THEIR MECHANISTIC UNDERSTANDING IS THE RECOGNITION THAT MANY CHEMICALS PROVOKE BOTH EFFECTS BY ELECTROPHILIC ATTACK TO THE BIOLOGICAL MACROMOLECULES, AS SUCH OR AFTER METABOLISM (GENOTOXIC CARCINOGENICITY). QSARS OF INDIVIDUAL CLASSES OF GENOTOXIC CARCINOGENS HAVE CONTRIBUTED TO THE ELUCIDATION OF THE CHEMICAL DETERMINANTS OF THIS ACTIVITY. LITTLE WORK HAS BEEN DONE ON THE EPIGENETIC CARCINOGENS, ACTING THROUGH NON-GENOTOXIC, VERY SPECIFIC MECHANISMS. HOWEVER, THE EXISTING QSARS FOR INDIVIDUAL CHEMICAL CLASSES ARE TOO FEW TO BE OF REAL USEFULNESS IN THE SCREENING OF MASSES OF CANDIDATE DRUGS. MODELS FOR PREDICTING THE CARCINOGENICITY OF "ANY TYPE" OF CHEMICALS HAVE BEEN PROPOSED: PROSPECTIVE PREDICTION EXERCISES POINTED TO THE SERIOUS LIMITATIONS OF MOST OF THESE APPROACHES. THE BEST ALTERNATIVE IS PROVIDED BY PANELS OF HUMAN EXPERTS. THE ABOVE PREDICTION EXERCISES CONSIDERED SAMPLES OF GENERAL CHEMICALS, THUS WE SPECIFICALLY ADDRESSED IN THIS PAPER THE ISSUE OF PHARMACEUTICAL DRUGS. WE APPLIED OUR EXPERT KNOWLEDGE TO A DATABASE OF DRUGS WHOSE CARCINOGENICITY/NONCARCINOGENICITY STATUS WAS KNOWN. WHEREAS MOST OF THE NONCARCINOGENS WERE CORRECTLY IDENTIFIED, OUR PREDICTION OF CARCINOGENS WAS LESS SUCCESSFUL THAN WITH THE GENERAL CHEMICALS. SEVERAL CARCINOGENIC DRUGS DID NOT SHOW RECOGNIZED STRUCTURAL ALERTS, AND SUPPOSEDLY ACTED BY EPIGENETIC MECHANISMS. WHEREAS THE CONTRIBUTION OF HUMAN EXPERTS IS HIGHLY VALUABLE IN THIS PHASE (E.G. PRIORITY SETTING), MORE WORK IS NECESSARY ON: A) EPIGENETIC CARCINOGENS; B) EFFICIENT COMPUTERIZED MODELS. 2003 10 5038 26 PHARMACOGENETICS OF CHRONIC PAIN AND ITS TREATMENT. THIS PAPER REVIEWS THE IMPACT OF GENETIC VARIABILITY OF DRUG METABOLIZING ENZYMES, TRANSPORTERS, RECEPTORS, AND PATHWAYS INVOLVED IN CHRONIC PAIN PERCEPTION ON THE EFFICACY AND SAFETY OF ANALGESICS AND OTHER DRUGS USED FOR CHRONIC PAIN TREATMENT. SEVERAL CANDIDATE GENES HAVE BEEN IDENTIFIED IN THE LITERATURE, WHILE THERE IS USUALLY ONLY LIMITED CLINICAL EVIDENCE SUBSTANTIATING FOR THE PENETRATION OF THE TESTING FOR THESE CANDIDATE BIOMARKERS INTO THE CLINICAL PRACTICE. FURTHER, THE PAIN-PERCEPTION REGULATION AND MODULATION ARE STILL NOT FULLY UNDERSTOOD, AND THUS MORE COMPLEX KNOWLEDGE OF GENETIC AND EPIGENETIC BACKGROUND FOR ANALGESIA WILL BE NEEDED PRIOR TO THE CLINICAL USE OF THE CANDIDATE GENETIC BIOMARKERS. 2013 11 2586 29 EPIGENETICS OF PAIN MEDIATORS. PURPOSE OF REVIEW: THE FIELD OF EPIGENETICS CONTINUES ITS INFLUENTIAL RISE AS A MEANS TO BETTER UNDERSTAND AN ORGANISM'S UNIQUE DEVELOPMENTAL IDENTITY OVER A LIFESPAN. WHEREAS A GENOME IS CONSTANT AND UNCHANGING, AN EPIGENOME IS DYNAMIC AND ALTERABLE. EPIGENETIC CHANGES ARE IN RESPONSE TO INNUMERABLE INTERNAL AND EXTERNAL INFLUENCES INCLUDING ENVIRONMENTAL CHANGES SUCH AS DIET, EXERCISE, DISEASE, TOXINS, AND STRESS. EPIGENETICS IS OF PARTICULAR INTEREST IN THE MEDICAL RESEARCH COMMUNITY BOTH FOR THE POTENTIAL TO CAUSE DISEASE AND AS A TARGET FOR THERAPEUTIC INTERVENTIONS. THIS ARTICLE PROVIDES A SUCCINCT EXPLANATION OF THE POTENTIAL FOR EPIGENETICS TO INFLUENCE THE UNDERSTANDING OF PAIN AS WELL AS A REVIEW OF RELEVANT RESEARCH ON THE TOPIC. RECENT FINDINGS: STUDIES ON EPIGENETICS AND PAIN REMAIN LARGELY PRECLINICAL AND INVESTIGATE THE THEORETICAL ABILITY OF EPIGENETICS TO ALTER THE NOCICEPTIVE PATHWAYS BOTH IN THE PERIPHERY AND CENTRALLY. SIGNIFICANT EVIDENCE NOW EXISTS FOR THE ABILITY OF EPIGENETICS TO MODIFY BROADLY CATEGORIZED PAIN TYPES, INCLUDING INFLAMMATORY, NEUROPATHIC, VISCERAL, AND CANCER RELATED. SUMMARY: BOTH PATIENTS AND PROVIDERS RECOGNIZE THAT NOVEL MEDICATIONS FOR THE TREATMENT OF BOTH ACUTE AND CHRONIC PAIN CONDITIONS ARE SORELY NEEDED. THE UNDERSTANDING OF EPIGENETICS AND ITS INFLUENCE ON NOCICEPTION REMAINS IN RELATIVE INFANCY BUT EARLY EVIDENCE IS STRONG FOR POTENTIAL THERAPEUTIC BENEFITS TO TREAT THESE CONDITIONS. 2018 12 6459 25 TIME TO CHANGE FROM A SIMPLE LINEAR MODEL TO A COMPLEX SYSTEMS MODEL. A SIMPLE LINEAR MODEL TO TEST THE HYPOTHESIS BASED ON ONE-ON-ONE RELATIONSHIP HAS BEEN USED TO FIND THE CAUSATIVE FACTORS OF DISEASES. HOWEVER, WE NOW KNOW THAT NOT JUST ONE, BUT MANY FACTORS FROM DIFFERENT SYSTEMS SUCH AS CHEMICAL EXPOSURE, GENES, EPIGENETIC CHANGES, AND PROTEINS ARE INVOLVED IN THE PATHOGENESIS OF CHRONIC DISEASES SUCH AS DIABETES MELLITUS. SO, WITH AVAILABILITY OF MODERN TECHNOLOGIES TO UNDERSTAND THE INTRICATE NATURE OF RELATIONS AMONG COMPLEX SYSTEMS, WE NEED TO MOVE FORWARD TO THE FUTURE BY TAKING COMPLEX SYSTEMS MODEL. 2016 13 6137 35 THE EPIGENETICS OF PSYCHOSIS: A STRUCTURED REVIEW WITH REPRESENTATIVE LOCI. THE EVIDENCE FOR AN ENVIRONMENTAL COMPONENT IN CHRONIC PSYCHOTIC DISORDERS IS STRONG AND RESEARCH ON THE EPIGENETIC MANIFESTATIONS OF THESE ENVIRONMENTAL IMPACTS HAS COMMENCED IN EARNEST. IN REVIEWING THIS RESEARCH, THE FOCUS IS ON THREE GENES AS MODELS FOR DIFFERENTIAL METHYLATION, MCHR1, AKT1 AND TDO2, EACH OF WHICH HAVE BEEN INVESTIGATED FOR GENETIC ASSOCIATION WITH PSYCHOTIC DISORDERS. ENVIRONMENTAL FACTORS ASSOCIATED WITH PSYCHOTIC DISORDERS, AND WHICH INTERACT WITH THESE MODEL GENES, ARE EXPLORED IN DEPTH. THE LOCATION OF TRANSCRIPTION FACTOR MOTIFS RELATIVE TO KEY METHYLATION SITES IS EVALUATED FOR PREDICTED GENE EXPRESSION RESULTS, AND FOR OTHER SITES, EVIDENCE IS PRESENTED FOR METHYLATION DIRECTING ALTERNATIVE SPLICING. EXPERIMENTAL RESULTS FROM KEY STUDIES SHOW DIFFERENTIAL METHYLATION: FOR MCHR1, IN PSYCHOSIS CASES VERSUS CONTROLS; FOR AKT1, AS A PRE-EXISTING METHYLATION PATTERN INFLUENCING BRAIN ACTIVATION FOLLOWING ACUTE ADMINISTRATION OF A PSYCHOSIS-ELICITING ENVIRONMENTAL STIMULUS; AND FOR TDO2, IN A PATTERN ASSOCIATED WITH A DEVELOPMENTAL FACTOR OF RISK FOR PSYCHOSIS, IN ALL CASES THE PREDICTED EXPRESSION IMPACT BEING HIGHLY DEPENDENT ON LOCATION. METHYLATION INDUCED BY SMOKING, A CONFOUNDING VARIABLE, EXHIBITS AN INTRIGUING PATTERN FOR ALL THREE GENES. FINALLY, HOW DIFFERENTIAL METHYLATION MESHES WITH DARWINIAN PRINCIPLES IS EXAMINED, IN PARTICULAR AS IT RELATES TO THE "FLEXIBLE STEM" THEORY OF EVOLUTION. 2022 14 3801 32 INTERPLAY OF VITAMIN D AND SIRT1 IN TISSUE-SPECIFIC METABOLISM-POTENTIAL ROLES IN PREVENTION AND TREATMENT OF NON-COMMUNICABLE DISEASES INCLUDING CANCER. THE IMPORTANCE OF THE PREVENTION AND CONTROL OF NON-COMMUNICABLE DISEASES, INCLUDING OBESITY, METABOLIC SYNDROME, TYPE 2 DIABETES, CARDIOVASCULAR DISEASES, AND CANCER, IS INCREASING AS A REQUIREMENT OF THE AGING POPULATION IN DEVELOPED COUNTRIES AND THE SUSTAINABILITY OF HEALTHCARE. SIMILARLY, THE 2013-2030 ACTION PLAN OF THE WHO FOR THE PREVENTION AND CONTROL OF NON-COMMUNICABLE DISEASES SEEKS THESE ACHIEVEMENTS. ADEQUATE LIFESTYLE CHANGES, ALONE OR WITH THE NECESSARY TREATMENTS, COULD REDUCE THE RISK OF MORTALITY OR THE DETERIORATION OF QUALITY OF LIFE. IN OUR RECENT WORK, WE SUMMARIZED THE ROLE OF TWO CENTRAL FACTORS, I.E., APPROPRIATE LEVELS OF VITAMIN D AND SIRT1, WHICH ARE CONNECTED TO ADEQUATE LIFESTYLES WITH BENEFICIAL EFFECTS ON THE PREVENTION AND CONTROL OF NON-COMMUNICABLE DISEASES. BOTH OF THESE FACTORS HAVE RECEIVED INCREASED ATTENTION IN RELATION TO THE COVID-19 PANDEMIC AS THEY BOTH TAKE PART IN REGULATION OF THE MAIN METABOLIC PROCESSES, I.E., LIPID/GLUCOSE/ENERGY HOMEOSTASIS, OXIDATIVE STRESS, REDOX BALANCE, AND CELL FATE, AS WELL AS IN THE HEALTHY REGULATION OF THE IMMUNE SYSTEM. VITAMIN D AND SIRT1 HAVE DIRECT AND INDIRECT INFLUENCE OF THE REGULATION OF TRANSCRIPTION AND EPIGENETIC CHANGES AND ARE RELATED TO CYTOPLASMIC SIGNALING PATHWAYS SUCH AS PLC/DAG/IP3/PKC/MAPK, MEK/ERK, INSULIN/MTOR/CELL GROWTH, PROLIFERATION; LEPTIN/PI3K-AKT-MTORC1, AKT/NFKB/COX-2, NFKB/TNFALPHA, IL-6, IL-8, IL-1BETA, AND AMPK/PGC-1ALPHA/GLUT4, AMONG OTHERS. THROUGH THEIR PROPER REGULATION, THEY MAINTAIN NORMAL BODY WEIGHT, LIPID PROFILE, INSULIN SECRETION AND SENSITIVITY, BALANCE BETWEEN THE PRO- AND ANTI-INFLAMMATORY PROCESSES UNDER NORMAL CONDITIONS AND INFECTIONS, MAINTAIN ENDOTHELIAL HEALTH; BALANCE CELL DIFFERENTIATION, PROLIFERATION, AND FATE; AND BALANCE THE CIRCADIAN RHYTHM OF THE CELLULAR METABOLISM. THE ROLE OF THESE TWO MOLECULES IS INTERCONNECTED IN THE MOLECULAR NETWORK, AND THEY REGULATE EACH OTHER IN SEVERAL LAYERS OF THE HOMEOSTASIS OF ENERGY AND THE CELLULAR METABOLISM. BOTH HAVE A CENTRAL ROLE IN THE MAINTENANCE OF HEALTHY AND BALANCED IMMUNE REGULATION AND REDOX REACTIONS; THEREFORE, THEY COULD CONSTITUTE PROMISING TARGETS EITHER FOR PREVENTION OR AS COMPLEMENTARY THERAPIES TO ACHIEVE A BETTER QUALITY OF LIFE, AT ANY AGE, FOR HEALTHY PEOPLE AND PATIENTS UNDER CHRONIC CONDITIONS. 2023 15 4209 37 METALLOTHIONEIN 2A GENE POLYMORPHISMS IN RELATION TO DISEASES AND TRACE ELEMENT LEVELS IN HUMANS. HUMAN METALLOTHIONEINS ARE A SUPERFAMILY OF LOW MOLECULAR WEIGHT INTRACELLULAR PROTEINS, WHOSE SYNTHESIS CAN BE INDUCED BY ESSENTIAL ELEMENTS (PRIMARILY ZN AND CU), TOXIC ELEMENTS AND CHEMICAL AGENTS, AND STRESS-PRODUCING CONDITIONS. OF THE FOUR KNOWN ISOFORMS IN THE HUMAN BODY MT2 IS THE MOST COMMON. THE EXPRESSION OF METALLOTHIONEINS IS ENCODED BY A MULTIGENE FAMILY OF LINKED GENES AND CAN BE INFLUENCED BY SINGLE NUCLEOTIDE POLYMORPHISMS (SNPS) IN THESE GENES. TO DATE, 24 SNPS IN THE MT2A GENE HAVE BEEN IDENTIFIED WITH THE INCIDENCE OF ABOUT 1 % IN VARIOUS POPULATION GROUPS, AND THREE OF THEM WERE SHOWN TO AFFECT PHYSIOLOGICAL AND PATHOPHYSIOLOGICAL PROCESSES. THIS REVIEW SUMMARISES CURRENT KNOWLEDGE ABOUT THESE THREE SNPS IN THE MT2A GENE AND THEIR ASSOCIATIONS WITH ELEMENT CONCENTRATIONS IN THE BODY OF HEALTHY AND DISEASED PERSONS. THE MOST INVESTIGATED SNP IS RS28366003 (MT2A -5 A/G). REPORTS ASSOCIATE IT WITH LONGEVITY, CANCER (BREAST, PROSTATE, LARYNGEAL, AND IN PARANASAL SINUSES), AND CHRONIC RENAL DISEASE. THE SECOND MOST INVESTIGATED SNP, RS10636 (MT2A +838G/C), IS ASSOCIATED WITH BREAST CANCER, CARDIOVASCULAR DISEASE, AND TYPE 2 DIABETES. BOTH ARE ALSO ASSOCIATED WITH SEVERAL METAL/METALLOID CONCENTRATIONS IN THE ORGANISM. THE THIRD SNP, RS1610216 (MT2A -209A/G), HAS BEEN STUDIED FOR ASSOCIATION WITH TYPE 2 DIABETES, CARDIOMYOPATHY, HYPERGLYCAEMIA, AND ZN CONCENTRATIONS. METALLOTHIONEIN CONCENTRATIONS AND MT2A POLYMORPHISMS HAVE A POTENTIAL TO BE USED AS BIOMARKERS OF METAL EXPOSURE AND CLINICAL MARKERS OF A NUMBER OF CHRONIC DISEASES. THIS POTENTIAL NEEDS TO BE STUDIED AND VERIFIED IN A LARGE NUMBER OF WELL-DEFINED GROUPS OF PARTICIPANTS (SEVERAL HUNDREDS AND THOUSANDS) WITH A FOCUS ON PARTICULAR PHYSIOLOGICAL OR PATHOLOGICAL CONDITION AND TAKING INTO CONSIDERATION OTHER CONTRIBUTING FACTORS, SUCH AS ENVIRONMENTAL EXPOSURE AND INDIVIDUAL GENETIC AND EPIGENETIC MAKEUP. 2020 16 1524 25 DNA METHYLATION CHANGES IN CYSTIC FIBROSIS: CAUSE OR CONSEQUENCE? TWIN AND SIBLING STUDIES HAVE SHOWN THAT LUNG DISEASE SEVERITY IS VARIABLE AMONG CYSTIC FIBROSIS (CF) PATIENTS AND AFFECTED TO THE SAME EXTENT BY GENETIC AND NONHERITABLE FACTORS. GENETIC FACTORS HAVE BEEN THOROUGHLY ASSESSED, WHEREAS THE MOLECULAR MECHANISMS WHEREBY NONHERITABLE FACTORS CONTRIBUTE TO THE PHENOTYPIC VARIABILITY OF CF PATIENTS ARE STILL UNKNOWN. EPIGENETIC MODIFICATIONS MAY REPRESENT THE MISSING LINK BETWEEN NONHERITABLE FACTORS AND PHENOTYPIC VARIATION IN CF. HEREIN, WE REVIEW RECENT STUDIES SHOWING THAT DNA METHYLATION IS ALTERED IN CF AND WE ADDRESS THREE POSSIBLE FACTORS RESPONSIBLE FOR THESE VARIATIONS: (I) OVERPRODUCTION OF REACTIVE OXYGEN SPECIES, (II) DEPLETION OF DNA METHYLATION COFACTORS AND (III) SUSCEPTIBILITY TO ACUTE AND CHRONIC BACTERIAL INFECTIONS. ALSO, WE HYPOTHESIZE THAT THE UNIQUE DNA METHYLATION PROFILE OF EACH PATIENT CAN MODULATE THE PHENOTYPE AND DISCUSS THE INTEREST OF IMPLEMENTING INTEGRATED GENOMIC, EPIGENOMIC AND TRANSCRIPTOMIC STUDIES TO FURTHER UNDERSTAND THE CLINICAL DIVERSITY OF CF PATIENTS (GRAPHICAL ABSTRACT). 2020 17 2279 37 EPIGENETIC REGULATION IN ALLERGIC DISEASES AND RELATED STUDIES. ASTHMA, A CHRONIC INFLAMMATORY DISORDER OF THE AIRWAY, HAS FEATURES OF BOTH HERITABILITY AS WELL AS ENVIRONMENTAL INFLUENCES WHICH CAN BE INTRODUCED IN UTERO EXPOSURES AND MODIFIED THROUGH AGING, AND THE FEATURES MAY ATTRIBUTE TO EPIGENETIC REGULATION. EPIGENETIC REGULATION EXPLAINS THE ASSOCIATION BETWEEN EARLY PRENATAL MATERNAL SMOKING AND LATER ASTHMA-RELATED OUTCOMES. EPIGENETIC MARKS (DNA METHYLATION, MODIFICATIONS OF HISTONE TAILS OR NONCODING RNAS) WORK WITH OTHER COMPONENTS OF THE CELLULAR REGULATORY MACHINERY TO CONTROL THE LEVELS OF EXPRESSED GENES, AND SEVERAL ALLERGY- AND ASTHMA-RELATED GENES HAVE BEEN FOUND TO BE SUSCEPTIBLE TO EPIGENETIC REGULATION, INCLUDING GENES IMPORTANT TO T-EFFECTOR PATHWAYS (IFN-GAMMA, INTERLEUKIN [IL] 4, IL-13, IL-17) AND T-REGULATORY PATHWAYS (FOXP3). THEREFORE, THE MECHANISM BY WHICH EPIGENETIC REGULATION CONTRIBUTES TO ALLERGIC DISEASES IS A CRITICAL ISSUE. IN THE PAST MOST PUBLISHED EXPERIMENTAL WORK, WITH FEW EXCEPTIONS, HAS ONLY COMPRISED SMALL OBSERVATIONAL STUDIES AND MODELS IN CELL SYSTEMS AND ANIMALS. HOWEVER, VERY RECENTLY EXCITING AND ELEGANT EXPERIMENTAL STUDIES AND NOVEL TRANSLATIONAL RESEARCH WORKS WERE PUBLISHED WITH NEW AND ADVANCED TECHNOLOGIES INVESTIGATING EPIGENETIC MARK ON A GENOMIC SCALE AND COMPREHENSIVE APPROACHES TO DATA ANALYSIS. INTERESTINGLY, A POTENTIAL LINK BETWEEN EXPOSURE TO ENVIRONMENTAL POLLUTANTS AND THE OCCURRENCE OF ALLERGIC DISEASES IS REVEALED RECENTLY, PARTICULAR IN DEVELOPED AND INDUSTRIALIZED COUNTRIES, AND ENDOCRINE DISRUPTING CHEMICALS (EDCS) AS ENVIRONMENTAL HORMONE MAY PLAY A KEY ROLE. THIS REVIEW ADDRESSES THE IMPORTANT QUESTION OF HOW EDCS (NONYLPHENOL, 4 OCTYLPHENOL, AND PHTHALATES) INFLUENCES ON ASTHMA-RELATED GENE EXPRESSION VIA EPIGENETIC REGULATION IN IMMUNE CELLS, AND HOW ANTI-ASTHMATIC AGENTS PROHIBIT EXPRESSION OF INFLAMMATORY GENES VIA EPIGENETIC MODIFICATION. THE DISCOVERY AND VALIDATION OF EPIGENETIC BIOMARKERS LINKING EXPOSURE TO ALLERGIC DISEASES MIGHT LEAD TO BETTER EPIGENOTYPING OF RISK, PROGNOSIS, TREATMENT PREDICTION, AND DEVELOPMENT OF NOVEL THERAPIES. 2014 18 6334 25 THE ROLE OF DNA METHYLATION AND HYDROXYMETHYLATION IN IMMUNOSENESCENCE. A HEALTHY FUNCTIONING IMMUNE SYSTEM IS CRITICAL TO STAVE OFF INFECTIOUS DISEASES, BUT AS HUMANS AND OTHER ORGANISMS AGE, THEIR IMMUNE SYSTEMS DECLINE. AS A RESULT, DISEASES THAT WERE READILY THWARTED IN EARLY LIFE POSE NONTRIVIAL HARM AND CAN EVEN BE DEADLY IN LATE LIFE. IMMUNOSENESCENCE IS DEFINED AS THE GENERAL DETERIORATION OF THE IMMUNE SYSTEM WITH AGE, AND IT IS CHARACTERIZED BY FUNCTIONAL CHANGES IN HEMATOPOIETIC STEM CELLS (HSCS) AND SPECIFIC BLOOD CELL TYPES AS WELL AS CHANGES IN LEVELS OF NUMEROUS FACTORS, PARTICULARLY THOSE INVOLVED IN INFLAMMATION. POTENTIAL MECHANISMS UNDERLYING IMMUNOSENESCENCE INCLUDE EPIGENETIC CHANGES SUCH AS CHANGES IN DNA METHYLATION (DNAM) AND DNA HYDROXYMETHYLATION (DNAHM) THAT OCCUR WITH AGE. THE PURPOSE OF THIS REVIEW IS TO DESCRIBE WHAT IS CURRENTLY KNOWN ABOUT THE RELATIONSHIP BETWEEN IMMUNOSENESCENCE AND THE AGE-RELATED CHANGES TO DNAM AND DNAHM, AND TO DISCUSS EXPERIMENTAL APPROACHES BEST SUITED TO FILL GAPS IN OUR UNDERSTANDING. 2019 19 49 28 A CURRENT GENETIC AND EPIGENETIC VIEW ON HUMAN AGING MECHANISMS. THE PROCESS OF AGING IS ONE OF THE MOST COMPLEX AND INTRIGUING BIOLOGICAL PHENOMENONS. AGING IS A GENETICALLY REGULATED PROCESS IN WHICH THE ORGANISM'S MAXIMUM LIFESPAN POTENTIAL IS PRE-DETERMINED, WHILE THE RATE OF AGING IS INFLUENCED BY ENVIRONMENTAL FACTORS AND LIFESTYLE. CONSIDERING THE COMPLEXITY OF MECHANISMS INVOLVED IN THE REGULATION OF AGING PROCESS, UP TO THIS DATE THERE ISN'T A MAJOR, UNIFYING THEORY WHICH COULD EXPLAIN THEM. AS GENETIC/EPIGENETIC AND ENVIRONMENTAL FACTORS BOTH INEVITABLY INFLUENCE THE AGING PROCESS, HERE WE PRESENT A REVIEW ON THE GENETIC AND EPIGENETIC REGULATION OF THE MOST IMPORTANT MOLECULAR AND CELLULAR MECHANISMS INVOLVED IN THE PROCESS OF AGING. BASED ON THE STUDIES ON OXIDATIVE STRESS, METABOLISM, GENOME STABILITY, EPIGENETIC MODIFICATIONS AND CELLULAR SENESCENCE IN ANIMAL MODELS AND HUMANS, WE GIVE AN OVERVIEW OF KEY GENETIC AND MOLECULAR PATHWAYS RELATED TO AGING. AS MOST OF GENETIC MANIPULATIONS WHICH INFLUENCE THE AGING PROCESS ALSO AFFECT REPRODUCTION, WE DISCUSS AGING IN HUMANS AS A POST-REPRODUCTIVE GENETICALLY DETERMINED PROCESS. AFTER THE AGE OF REPRODUCTIVE SUCCESS, AGING CONTINOUSLY PROGRESSES WHICH CLINICALLY COINCIDES WITH THE ONSET OF MOST CHRONIC DISEASES, CANCERS AND DEMENTIONS. AS EVOLUTION SHAPES THE GENOMES FOR REPRODUCTIVE SUCCESS AND NOT FOR POST-REPRODUCTIVE SURVIVAL, AGING COULD BE DEFINED AS A PROTECTIVE MECHANISM WHICH ENSURES THE PRESERVATION AND PROGRESS OF SPECIES THROUGH THE MODIFICATION, TRASMISSION AND IMPROVEMENT OF GENETIC MATERIAL. 2009 20 3020 30 GENETICS AND EPIGENETICS OF OSTEOARTHRITIS. OSTEOARTHRITIS (OA) IS A COMMON AGE-RELATED DISEASE THAT AFFECTS THE TISSUES OF THE SYNOVIAL JOINT, LEADING TO LOSS OF FUNCTION AND PAIN. IT IMPACTS ON BOTH PATIENT MORBIDITY AND MORTALITY. IT IS A COMPLEX, POLYGENIC DISEASE THAT LACKS ANY LARGE-EFFECT SUSCEPTIBILITY LOCI. INSTEAD, OA SUSCEPTIBILITY ALLELES INDIVIDUALLY CONTRIBUTE ONLY MODESTLY TO THE OVERALL DISEASE RISK, MAKING THEIR IDENTIFICATION CHALLENGING. DESPITE THIS, BREAKTHROUGHS HAVE OCCURRED WITH COMPELLING ASSOCIATIONS SO FAR REPORTED TO POLYMORPHISMS WITHIN THE GENES GDF5 AND MCF2L AND TO THE GENOMIC REGION 7Q22. THE LATTER TWO HAVE EMERGED FROM GENOME-WIDE ASSOCIATION SCANS, WHICH ARE LIKELY TO YIELD MORE HITS IN THE NEAR FUTURE. AS FOR MANY COMPLEX DISEASES, IT IS NOW APPARENT THAT EPIGENETIC EFFECTS ARE ALSO IMPORTANT MEDIATORS OF DISEASE BIOLOGY, WITH DNA METHYLATION, HISTONE MODIFICATIONS AND NON-CODING RNAS ALL HAVING A ROLE. AT PRESENT, MUCH OF THE EPIGENETIC FOCUS HAS BEEN ON CARTILAGE, THE TISSUE AT THE CENTER OF THE OA DISEASE PROCESS. IF WE ARE TO GET CLOSE TO A QUALITATIVE AND QUANTITATIVE UNDERSTANDING OF THE IMPACT OF EPIGENETICS ON OA, THEN IN FUTURE THE OTHER TISSUES OF THE JOINT WILL ALSO NEED TO BE INVESTIGATED. ONE OF THE MORE EXCITING INSIGHTS TO HAVE EMERGED RECENTLY IS THE FACT THAT EPIGENETIC EFFECTS CAN IMPACT ON OA GENETIC EFFECTS AND THIS MAY BE A PARTICULARLY FRUITFUL AVENUE FOR INTEGRATING BOTH AS WE MOVE TOWARD A CLEARER UNDERSTANDING OF THE PATHOPHYSIOLOGY OF THIS INTRIGUING DISEASE. 2012