1 524 133 ASSOCIATIONS OF BDNF GENOTYPE AND PROMOTER METHYLATION WITH ACUTE AND LONG-TERM STROKE OUTCOMES IN AN EAST ASIAN COHORT. BACKGROUND: BRAIN DERIVED NEUROTROPHIC FACTOR (BDNF) HAS BEEN SHOWN TO PLAY AN IMPORTANT ROLE IN POSTSTROKE RECOVERY. BDNF SECRETION IS INFLUENCED BY GENETIC AND EPIGENETIC PROFILES. THIS STUDY AIMED TO INVESTIGATE WHETHER BDNF VAL66MET POLYMORPHISM AND PROMOTER METHYLATION STATUS WERE ASSOCIATED WITH OUTCOMES AT TWO WEEKS AND ONE YEAR AFTER STROKE. METHODS AND FINDINGS: A TOTAL OF 286 PATIENTS WERE EVALUATED AT THE TIME OF ADMISSION AND TWO WEEKS AFTER STROKE, AND 222 (78%) WERE FOLLOWED ONE YEAR LATER IN ORDER TO EVALUATE CONSEQUENCES OF STROKE AT BOTH ACUTE AND CHRONIC STAGES. STROKE OUTCOMES WERE DICHOTOMISED INTO GOOD AND POOR BY THE MODIFIED RANKIN SCALE. STROKE SEVERITY (NATIONAL INSTITUTES OF HEALTH STROKE SCALE), PHYSICAL DISABILITY (BARTHEL INDEX), AND COGNITIVE FUNCTION (MINI-MENTAL STATE EXAMINATION) WERE MEASURED. ASSOCIATIONS OF BDNF GENOTYPE AND METHYLATION STATUS ON STROKE OUTCOMES AND ASSESSMENT SCALE SCORES WERE INVESTIGATED USING LOGISTIC REGRESSION, REPEATED MEASURES ANOVA AND PARTIAL CORRELATION TESTS. BDNF VAL66MET POLYMORPHISM WAS INDEPENDENTLY ASSOCIATED WITH POOR OUTCOME AT 2 WEEKS AND AT 1 YEAR, AND WITH WORSENING PHYSICAL DISABILITY AND COGNITIVE FUNCTION OVER THAT PERIOD. HIGHER BDNF PROMOTER METHYLATION STATUS WAS INDEPENDENTLY ASSOCIATED WITH WORSE OUTCOMES AT 1 YEAR, AND WITH THE WORSENING OF PHYSICAL DISABILITY AND COGNITIVE FUNCTION. NO SIGNIFICANT GENOTYPE-METHYLATION INTERACTIONS WERE FOUND. CONCLUSIONS: A ROLE FOR BDNF IN POSTSTROKE RECOVERY WAS SUPPORTED, AND CLINICAL UTILITY OF BDNF GENETIC AND EPIGENETIC PROFILE AS PROGNOSTIC BIOMARKERS AND A TARGET FOR DRUG DEVELOPMENT WAS SUGGESTED. 2012 2 67 60 A LONGITUDINAL STUDY OF THE ASSOCIATIONS OF BDNF GENOTYPE AND METHYLATION WITH POSTSTROKE ANXIETY. BACKGROUND: ALTHOUGH THE PRECISE ETIOLOGY OF POSTSTROKE ANXIETY (PSA) HAS YET TO BE FULLY ELUCIDATED, IT IS KNOWN THAT BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) IS IMPORTANT FOR NEURAL PLASTICITY AND LONG-TERM POTENTIATION, ASSOCIATED WITH THE PATHOPHYSIOLOGY OF ANXIETY. THE EXPRESSION OF BDNF IS REGULATED BY EPIGENETIC AND GENETIC PROFILES. THUS, WE INVESTIGATED THE ASSOCIATION BETWEEN BDNF METHYLATION STATUS AND PSA AT 2 WEEKS AND 1 YEAR AFTER STROKE WHILE ACCOUNTING FOR INTERACTIONS WITH THE BDNF VAL66MET POLYMORPHISM. METHODS: THE BASELINE SAMPLE COMPRISED 286 PATIENTS WHO WERE ASSESSED AT 2 WEEKS AFTER STROKE; OF THESE PATIENTS, 222 (78%) WERE FOLLOWED UP WITH AT 1 YEAR AFTER STROKE. THE PRESENCE OF PSA WAS DETERMINED USING THE ANXIETY SUBSCALE OF THE HOSPITAL ANXIETY AND DEPRESSION SCALE (HADS), AND THE EFFECTS OF BDNF METHYLATION STATUS AND POLYMORPHISMS ON PSA STATUS WERE ASSESSED WITH MULTIVARIATE LOGISTIC REGRESSION MODELS. RESULTS: THE PREVALENCE OF PSA WAS SLIGHTLY LOWER (27 [9.4%]) AT BASELINE, AND 35 (15.8%) PATIENTS WERE IDENTIFIED AS HAVING PSA AT THE 1-YEAR FOLLOW-UP. STROKE PATIENTS WITH A HIGHER AVERAGE METHYLATION STATUS WERE MORE LIKELY TO HAVE PSA AT 1 YEAR. THE BDNF VAL66MET POLYMORPHISM WAS NOT INDEPENDENTLY ASSOCIATED WITH PSA DURING EITHER THE ACUTE OR CHRONIC PHASE AFTER STROKE, BUT THERE WAS A SIGNIFICANT INTERACTIVE EFFECT BETWEEN BDNF METHYLATION AND GENOTYPE ON PSA AT 2 WEEKS. CONCLUSIONS: IN THIS STUDY, BDNF METHYLATION IN COMBINATION WITH THE MET/MET BDNF POLYMORPHISM (VAL66MET POLYMORPHISM) WAS ASSOCIATED WITH PSA. THESE FINDINGS MAY HELP IDENTIFY PATIENTS AT HIGHER RISK FOR PSA. 2019 3 344 42 ALTERED BDNF METHYLATION IN PATIENTS WITH CHRONIC MUSCULOSKELETAL PAIN AND HIGH BIOPSYCHOSOCIAL COMPLEXITY. PURPOSE: THE INTERMED INSTRUMENT, WHICH WAS DEVELOPED TO MEASURE PATIENT'S BIOPSYCHOSOCIAL (BPS) COMPLEXITY, REPRESENTS A POWERFUL DIAGNOSTIC AND THERAPEUTIC TOOL. EPIGENETIC CHANGES ARE THE INTERFACE BETWEEN SIGNALS FROM THE ENVIRONMENT AND GENETIC MODIFICATIONS, AFFECTING GENE EXPRESSION, IN PARTICULAR, BY DNA METHYLATION OF CPG DINUCLEOTIDES IN PROMOTOR REGIONS OF THE CORRESPONDING GENES. THE BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) GENE PLAYS A CRUCIAL ROLE IN THE CENTRAL SENSITIZATION (CS) OF PAIN. IN THIS STUDY, WE HYPOTHESIZED THAT CHRONIC PAIN MODIFIES THE METHYLATION LEVELS OF THE BDNF GENE IN A MANNER THAT IS INTERCONNECTED WITH THE BPS STATUS. PATIENTS AND METHODS: FIFTY-EIGHT CHRONIC MUSCULOSKELETAL PAIN PATIENTS (CMSP) WERE ENROLLED IN THE STUDY. DNA WAS EXTRACTED FROM BLOOD SAMPLES, THE METHYLATION LEVELS OF 13 CPG SITES IN THE BDNF PROMOTER WERE MEASURED BY PYROSEQUENCING, AND ASSOCIATION STUDIES WITH VARIOUS PATIENT PARAMETERS AND THE INTERMED SCORES WERE PERFORMED. RESULTS: INTERESTINGLY, A NEGATIVE CORRELATION (-0.40) WAS FOUND BETWEEN THE TOTAL INTERMED SCORES AND THE AVERAGE CPG METHYLATION VALUES OF THE BDNF GENE, BUT NO CORRELATION WAS OBSERVED WITH THE SEVERITY OF PAIN, DEGREE OF ANXIETY, DEPRESSION, OR KINESIOPHOBIA AND CATASTROPHISM. MOREOVER, THE ASSOCIATION WAS INDEPENDENT OF AGE, SEX AND LEVEL OF COMORBIDITIES. CONCLUSION: THIS RESULT SHOWS THAT CMSP, IN ASSOCIATION WITH ITS BIOPSYCHOSOCIAL CONTEXT, EPIGENETICALLY DECREASES THE DEGREE OF METHYLATION OF THE BDNF PROMOTER AND SHOULD THEREFORE INCREASE THE LEVEL OF BDNF TRANSCRIPTION. IT ALSO SUGGESTS A ROLE OF THE INTERMED TOOL TO DETECT A RELATIONSHIP BETWEEN THE BPS COMPLEXITY AND THE EPIGENETIC CONTROL OF A TARGET GENE. THE POSSIBLE UPREGULATION OF BDNF EXPRESSION MIGHT BE, AT LEAST IN PART, THE SIGNAL FOR CHRONIC PAIN-INDUCED CENTRAL SENSITIZATION (CS). THIS COULD PARTLY EXPLAIN WHY PATIENTS WITH A HIGHER LEVEL OF COMPLEXITY FEEL MORE PAIN THAN THOSE WITH LOWER COMPLEXITY. 2020 4 577 42 BDNF PROMOTER METHYLATION AND GENETIC VARIATION IN LATE-LIFE DEPRESSION. THE REGULATION OF THE BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) IS IMPORTANT FOR DEPRESSION PATHOPHYSIOLOGY AND EPIGENETIC REGULATION OF THE BDNF GENE MAY BE INVOLVED. THIS STUDY INVESTIGATED WHETHER BDNF METHYLATION IS A MARKER OF DEPRESSION. ONE THOUSAND AND TWENTY-FOUR PARTICIPANTS WERE RECRUITED AS PART OF A LONGITUDINAL STUDY OF PSYCHIATRIC DISORDERS IN GENERAL POPULATION ELDERLY (AGE ? 65). CLINICAL LEVELS OF DEPRESSION WERE ASSESSED USING THE MINI INTERNATIONAL NEUROPSYCHIATRIC INTERVIEW FOR THE DIAGNOSIS OF MAJOR DEPRESSIVE DISORDER ACCORDING TO THE DIAGNOSTIC AND STATISTICAL MANUAL OF MENTAL DISORDER IV CRITERIA, AND THE CENTRE FOR EPIDEMIOLOGIC STUDIES DEPRESSION SCALE (CES-D) FOR ASSESSMENT OF MODERATE TO SEVERE DEPRESSIVE SYMPTOMS. BUCCAL DNA METHYLATION AT THE TWO MOST WIDELY STUDIED BDNF PROMOTERS, I AND IV, WAS INVESTIGATED USING THE SEQUENOM MASSARRAY PLATFORM THAT ALLOWS HIGH-THROUGHPUT INVESTIGATION OF METHYLATION AT INDIVIDUAL CPG SITES WITHIN DEFINED GENOMIC REGIONS. IN MULTIVARIATE LINEAR REGRESSION ANALYSES ADJUSTED FOR A RANGE OF PARTICIPANT CHARACTERISTICS INCLUDING ANTIDEPRESSANT USE, DEPRESSION AT BASELINE, AS WELL AS CHRONIC LATE-LIFE DEPRESSION OVER THE 12-YEAR FOLLOW-UP, WERE ASSOCIATED WITH OVERALL HIGHER BDNF METHYLATION LEVELS, WITH TWO SITES SHOWING SIGNIFICANT ASSOCIATIONS (PROMOTER I, DELTA MEAN = 0.4%, P = 0.0002; PROMOTER IV, DELTA MEAN = 5.4%, P = 0.021). THREE SINGLE-NUCLEOTIDE POLYMORPHISMS (RS6265, RS7103411 AND RS908867) WERE ALSO FOUND TO MODIFY THE ASSOCIATION BETWEEN DEPRESSION AND PROMOTER I METHYLATION. AS ONE OF THE LARGEST EPIGENETIC STUDIES OF DEPRESSION, AND THE FIRST INVESTIGATING BDNF METHYLATION IN BUCCAL TISSUE, OUR FINDINGS HIGHLIGHT THE POTENTIAL FOR BUCCAL BDNF METHYLATION TO BE A BIOMARKER OF DEPRESSION. 2015 5 1537 29 DNA METHYLATION IN ADOLESCENTS WITH ANXIETY DISORDER: A LONGITUDINAL STUDY. ANXIETY DISORDERS (AD) TYPICALLY MANIFEST IN CHILDREN AND ADOLESCENTS AND MIGHT PERSIST INTO ADULTHOOD. HOWEVER, THERE ARE STILL FEW DATA CONCERNING EPIGENETIC MECHANISMS ASSOCIATED WITH ONSET, PERSISTENCE OR REMISSION OF AD OVER TIME. WE INVESTIGATED A COHORT OF ADOLESCENTS AND YOUNG ADULTS AT BASELINE (AGE; 13.19 +/- 2.38) AND AFTER 5 YEARS AND CLASSIFIED THEM ACCORDING TO THE AD DIAGNOSIS AND THEIR LONGITUDINAL TRAJECTORIES INTO 4 GROUPS: (1) TYPICALLY DEVELOPING COMPARISONS (TDC; CONTROL GROUP, N = 14); (2) INCIDENT (AD IN THE SECOND EVALUATION ONLY, N = 11); (3) PERSISTENT (AD IN BOTH EVALUATIONS, N = 14) AND (4) REMITTENT (AD IN THE FIRST EVALUATION ONLY, N = 8). DNA METHYLATION WAS EVALUATED WITH THE INFINIUM HUMANMETHYLATION450 BEADCHIP FROM SALIVA SAMPLES COLLECTED AT BOTH EVALUATIONS. GENE SET ENRICHMENT ANALYSIS WAS APPLIED TO CONSIDER BIOLOGICAL PATHWAYS. WE FOUND DECREASED DNA METHYLATION IN TDC GROUP WHILE THE CHRONIC CASES OF AD PRESENTED HYPERMETHYLATION IN CENTRAL NERVOUS SYSTEM DEVELOPMENT PATHWAYS. MOREOVER, WE SHOWED THAT THIS PERSISTENT GROUP ALSO PRESENTED HYPERMETHYLATION WHILE THE OTHER THREE GROUPS WERE ASSOCIATED WITH HYPOMETHYLATION IN NERVOUS SYSTEM DEVELOPMENT PATHWAY. INCIDENCE AND REMISSION GROUPS WERE ASSOCIATED WITH INCREASED AND DECREASED METHYLATION IN NEURON DEVELOPMENT PATHWAYS, RESPECTIVELY. LARGER STUDIES ARE LIKELY TO DETECT SPECIFIC GENES RELEVANT TO AD. 2018 6 1599 36 DNA METHYLATION SIGNATURE OF CHILDHOOD CHRONIC PHYSICAL AGGRESSION IN T CELLS OF BOTH MEN AND WOMEN. BACKGROUND: HIGH FREQUENCY OF PHYSICAL AGGRESSION IS THE CENTRAL FEATURE OF SEVERE CONDUCT DISORDER AND IS ASSOCIATED WITH A WIDE RANGE OF SOCIAL, MENTAL AND PHYSICAL HEALTH PROBLEMS. WE HAVE PREVIOUSLY TESTED THE HYPOTHESIS THAT DIFFERENTIAL DNA METHYLATION SIGNATURES IN PERIPHERAL T CELLS ARE ASSOCIATED WITH A CHRONIC AGGRESSION TRAJECTORY IN MALES. DESPITE THE FACT THAT SEX DIFFERENCES APPEAR TO PLAY A PIVOTAL ROLE IN DETERMINING THE DEVELOPMENT, MAGNITUDE AND FREQUENCY OF AGGRESSION, MOST OF PREVIOUS STUDIES FOCUSED ON MALES, SO LITTLE IS KNOWN ABOUT FEMALE CHRONIC PHYSICAL AGGRESSION. WE THEREFORE TESTED HERE WHETHER OR NOT THERE IS A SIGNATURE OF PHYSICAL AGGRESSION IN FEMALE DNA METHYLATION AND, IF THERE IS, HOW IT RELATES TO THE SIGNATURE OBSERVED IN MALES. METHODOLOGY/PRINCIPAL FINDINGS: METHYLATION PROFILES WERE CREATED USING THE METHOD OF METHYLATED DNA IMMUNOPRECIPITATION (MEDIP) FOLLOWED BY MICROARRAY HYBRIDIZATION AND STATISTICAL AND BIOINFORMATIC ANALYSES ON T CELL DNA OBTAINED FROM ADULT WOMEN WHO WERE FOUND TO BE ON A CHRONIC PHYSICAL AGGRESSION TRAJECTORY (CPA) BETWEEN 6 AND 12 YEARS OF AGE COMPARED TO WOMEN WHO FOLLOWED A NORMAL PHYSICAL AGGRESSION TRAJECTORY. WE CONFIRMED THE EXISTENCE OF A WELL-DEFINED, GENOME-WIDE SIGNATURE OF DNA METHYLATION ASSOCIATED WITH CHRONIC PHYSICAL AGGRESSION IN THE PERIPHERAL T CELLS OF ADULT FEMALES THAT INCLUDES MANY OF THE GENES SIMILARLY ASSOCIATED WITH PHYSICAL AGGRESSION IN THE SAME CELL TYPES OF ADULT MALES. CONCLUSIONS: THIS STUDY IN A SMALL NUMBER OF WOMEN PRESENTS PRELIMINARY EVIDENCE FOR A GENOME-WIDE VARIATION IN PROMOTER DNA METHYLATION THAT ASSOCIATES WITH CPA IN WOMEN THAT WARRANT LARGER STUDIES FOR FURTHER VERIFICATION. A SIGNIFICANT PROPORTION OF THESE ASSOCIATIONS WERE PREVIOUSLY OBSERVED IN MEN WITH CPA SUPPORTING THE HYPOTHESIS THAT THE EPIGENETIC SIGNATURE OF EARLY LIFE AGGRESSION IN FEMALES IS COMPOSED OF A COMPONENT SPECIFIC TO FEMALES AND ANOTHER COMMON TO BOTH MALES AND FEMALES. 2014 7 6311 30 THE RELATION BETWEEN DNA METHYLATION PATTERNS AND SERUM CYTOKINE LEVELS IN COMMUNITY-DWELLING ADULTS: A PRELIMINARY STUDY. BACKGROUND: THE LEVELS OF CIRCULATING CYTOKINES FLUCTUATE WITH AGE, ACUTE ILLNESS, AND CHRONIC DISEASE, AND ARE PREDICTIVE OF MORTALITY; THIS IS ALSO TRUE FOR PATTERNS OF DNA (CPG) METHYLATION. GIVEN THAT IMMUNE CELLS ARE PARTICULARLY SENSITIVE TO CHANGES IN THE CONCENTRATION OF CYTOKINES IN THEIR MICROENVIRONMENT, WE HYPOTHESIZED THAT SERUM LEVELS OF TNF, IL-6, IL-8 AND IL-10 WOULD CORRELATE WITH GENOME-WIDE ALTERATIONS IN THE DNA METHYLATION LEVELS OF BLOOD LEUKOCYTES. TO TEST THIS, WE EVALUATED COMMUNITY-DWELLING ADULTS (N = 14; 48-78 YEARS OLD) RECRUITED TO A PILOT STUDY FOR THE CANADIAN LONGITUDINAL STUDY ON AGING (CLSA), EXAMINING DNA METHYLATION PATTERNS IN PERIPHERAL BLOOD MONONUCLEAR CELLS USING THE ILLUMINA HUMANMETHYLATION 450 K BEADCHIP. RESULTS: WE SHOW THAT, APART FROM AGE, SERUM IL-10 LEVELS EXHIBITED THE MOST SUBSTANTIAL ASSOCIATION TO DNA METHYLATION PATTERNS, FOLLOWED BY TNF, IL-6 AND IL-8. FURTHERMORE, WHILE THE LEVELS OF THESE CYTOKINES WERE HIGHER IN ELDERLY ADULTS, NO ASSOCIATIONS WITH EPIGENETIC ACCELERATED AGING, DERIVED USING THE EPIGENETIC CLOCK, WERE OBSERVED. CONCLUSIONS: AS A PRELIMINARY STUDY WITH A SMALL SAMPLE SIZE, THE CONCLUSIONS DRAWN FROM THIS WORK MUST BE VIEWED WITH CAUTION; HOWEVER, OUR OBSERVATIONS ARE ENCOURAGING AND CERTAINLY WARRANT MORE SUITABLY POWERED STUDIES OF THIS RELATIONSHIP. 2017 8 5682 31 SHORT-TERM CHANGES IN GLOBAL METHYLATION AND HYDROXYMETHYLATION DURING ALCOHOL DETOXIFICATION. ALCOHOL DEPENDENCE IS A COMMON PUBLIC HEALTH PROBLEM AND EPIGENETICS MAY OFFER NEW ASPECTS IN UNDERSTANDING THE BIOLOGICAL AND GENETIC UNDERPINNINGS AND IMPROVE TREATMENT OF THIS COMPLEX DISEASE. SUPPOSEDLY, METHYLATION AND HYDROXYMETHYLATION ARE ALTERED IN BRAIN TISSUES AND IN SYNAPSE-RELATED GENES DUE TO CHRONIC ALCOHOL INTAKE AND DURING WITHDRAWAL. TO ASSESS POTENTIAL EPIGENETIC CHANGES AFTER CESSATION OF CHRONIC ALCOHOL INTAKE, WE COMPARED 23 ALCOHOL-DEPENDENT INDIVIDUALS DURING INPATIENT ALCOHOL DETOXIFICATION WITH 13 CAREFULLY MATCHED CONTROLS. BLOOD SAMPLES WERE TAKEN ON THE DAY OF ADMISSION, AFTER ONE AND AFTER TWO WEEKS AT THE END OF INPATIENT TREATMENT. GENOME-WIDE GLOBAL METHYLATION AND GLOBAL DNA HYDROXYMETHYLATION WERE COMPARED ACROSS GROUPS. THERE WERE SIGNIFICANT DIFFERENCES IN GLOBAL METHYLATION ACROSS TIME FROM ADMISSION TO ONE AND TWO WEEKS OF INPATIENT WITHDRAWAL (P < 0.001). THESE FINDINGS WERE PARALLELED TO CHANGES IN GLOBAL DNA HYDROXYMETHYLATION ACROSS TIME WHEN AGE WAS EMPLOYED AS A COFACTOR (P < 0.001). SEVERAL POTENTIALLY INFLUENCING VARIABLES LIKE SEVERITY OF WITHDRAWAL, DOSE OF WITHDRAWAL MEDICATION AND ALCOHOL INTAKE BEFORE ADMISSION DID NOT YIELD SIGNIFICANT INFLUENCE ON EPIGENETIC CHANGES. THE RESULTS CONFIRM PREVIOUS FINDINGS OF SIGNIFICANT ALTERATIONS OF EPIGENETIC PATTERNS DURING ALCOHOL INTOXICATION AND PRESENT FOR THE FIRST TIME HYDROXYMETHYLATION CHANGES IN THESE INDIVIDUALS. 2019 9 1967 37 EPIGENETIC ALTERATION OF THE DOPAMINE TRANSPORTER GENE IN ALCOHOL-DEPENDENT PATIENTS IS ASSOCIATED WITH AGE. CHRONIC ALCOHOL ABUSE AND DEPENDENCE ARE ASSOCIATED WITH DYSFUNCTIONAL DOPAMINERGIC NEUROTRANSMISSION IN MESOCORTICOLIMBIC CIRCUITS. GENETIC AND ENVIRONMENTAL FACTORS HAVE BEEN SHOWN TO MODULATE SUSCEPTIBILITY TO ALCOHOL DEPENDENCE, AND BOTH MAY ACT THROUGH EPIGENETIC MECHANISMS THAT CAN MODULATE GENE EXPRESSION, E.G. DNA METHYLATION AT CPG SITES. RECENT STUDIES HAVE SUGGESTED THAT DNA METHYLATION PATTERNS MAY CHANGE OVER TIME. HOWEVER, FEW DATA ARE AVAILABLE CONCERNING THE RATE OF THESE CHANGES IN SPECIFIC GENES. A RECENT STUDY FOUND THAT HYPERMETHYLATION OF THE PROMOTER OF THE DOPAMINE TRANSPORTER (DAT) GENE WAS POSITIVELY CORRELATED WITH ALCOHOL DEPENDENCE AND NEGATIVELY CORRELATED WITH ALCOHOL CRAVING. THE AIM OF THE PRESENT STUDY WAS TO REPLICATE THESE FINDINGS IN A LARGER SAMPLE OF ALCOHOL-DEPENDENT PATIENTS AND POPULATION-BASED CONTROLS MATCHED FOR AGE AND SEX. NO DIFFERENCE IN METHYLATION LEVEL WAS OBSERVED BETWEEN PATIENTS AND CONTROLS, AND NO DIFFERENCE IN METHYLATION LEVEL WAS OBSERVED BEFORE AND AFTER ALCOHOL WITHDRAWAL IN PATIENTS. HOWEVER, PATIENTS WITH MORE SEVERE CRAVING SHOWED A TREND TOWARDS LOWER DAT METHYLATION LEVELS (P = 0.07), WHICH IS CONSISTENT WITH PREVIOUS FINDINGS. FURTHERMORE, IN OUR OVERALL SAMPLE, DAT METHYLATION LEVELS INCREASED WITH AGE. INTERESTINGLY, A SEPARATE ANALYSIS OF PATIENTS SUGGESTED THAT THIS FINDING WAS MAINLY DRIVEN BY THE PATIENT GROUP. ALTHOUGH THE PRESENT DATA DO NOT CLARIFY WHETHER CHRONIC ALCOHOL ABUSE IS RESPONSIBLE FOR THIS PHENOMENON OR MERELY ENHANCES AN AGEING-SPECIFIC PROCESS, OUR FINDINGS SUGGEST THAT HYPERMETHYLATION IN ALCOHOL-DEPENDENT PATIENTS IS A CONSEQUENCE, RATHER THAN A CAUSE, OF THE DISORDER. 2014 10 990 29 CHRONIC SOCIAL STRESS INDUCES DNA METHYLATION CHANGES AT AN EVOLUTIONARY CONSERVED INTERGENIC REGION IN CHROMOSOME X. CHRONIC STRESS RESULTING FROM PROLONGED EXPOSURE TO NEGATIVE LIFE EVENTS INCREASES THE RISK OF MOOD AND ANXIETY DISORDERS. ALTHOUGH CHRONIC STRESS CAN CHANGE GENE EXPRESSION RELEVANT FOR BEHAVIOR, MOLECULAR REGULATORS OF THIS CHANGE HAVE NOT BEEN FULLY DETERMINED. ONE PROCESS THAT COULD PLAY A ROLE IS DNA METHYLATION, AN EPIGENETIC PROCESS WHEREBY A METHYL GROUP IS ADDED ONTO NUCLEOTIDES, PREDOMINANTLY CYTOSINE IN THE CPG CONTEXT, AND WHICH CAN BE INDUCED BY CHRONIC STRESS. IT IS UNKNOWN TO WHAT EXTENT CHRONIC SOCIAL DEFEAT, A MODEL OF HUMAN SOCIAL STRESS, INFLUENCES DNA METHYLATION PATTERNS ACROSS THE GENOME. OUR STUDY ADDRESSED THIS QUESTION BY USING A TARGETED-CAPTURE APPROACH CALLED METHYL-SEQ TO INVESTIGATE DNA METHYLATION PATTERNS OF THE DENTATE GYRUS AT PUTATIVE REGULATORY REGIONS ACROSS THE MOUSE GENOME FROM MICE EXPOSED TO 14 DAYS OF SOCIAL DEFEAT. FINDINGS WERE REPLICATED IN INDEPENDENT COHORTS BY BISULFITE-PYROSEQUENCING. TWO DIFFERENTIALLY METHYLATED REGIONS (DMRS) WERE IDENTIFIED. ONE DMR WAS LOCATED AT INTRON 9 OF DROSHA, AND IT SHOWED REDUCED METHYLATION IN STRESSED MICE. THIS OBSERVATION REPLICATED IN ONE OF TWO INDEPENDENT COHORTS. A SECOND DMR WAS IDENTIFIED AT AN INTERGENIC REGION OF CHROMOSOME X, AND METHYLATION IN THIS REGION WAS INCREASED IN STRESSED MICE. THIS METHYLATION DIFFERENCE REPLICATED IN TWO INDEPENDENT COHORTS AND IN MAJOR DEPRESSIVE DISORDER (MDD) POSTMORTEM BRAINS. THESE RESULTS HIGHLIGHT A REGION NOT PREVIOUSLY KNOWN TO BE DIFFERENTIALLY METHYLATED BY CHRONIC SOCIAL DEFEAT STRESS AND WHICH MAY BE INVOLVED IN MDD. 2018 11 5957 36 TELOMERE LENGTH AND EPIGENETIC AGE ACCELERATION IN ADOLESCENTS WITH ANXIETY DISORDERS. EVIDENCE ON THE RELATIONSHIP BETWEEN GENETICS AND MENTAL HEALTH ARE FLOURISHING. HOWEVER, FEW STUDIES ARE EVALUATING EARLY BIOMARKERS THAT MIGHT LINK GENES, ENVIRONMENT, AND PSYCHOPATHOLOGY. WE AIMED TO STUDY TELOMERE LENGTH (TL) AND EPIGENETIC AGE ACCELERATION (AA) IN A COHORT OF ADOLESCENTS WITH AND WITHOUT ANXIETY DISORDERS (N = 234). WE EVALUATED A REPRESENTATIVE SUBSAMPLE OF PARTICIPANTS AT BASELINE AND AFTER 5 YEARS (N = 76) AND CATEGORIZED THEM ACCORDING TO THEIR ANXIETY DISORDER DIAGNOSIS AT BOTH TIME POINTS: (1) CONTROL GROUP (NO ANXIETY DISORDER, N = 18), (2) VARIABLE GROUP (ANXIETY DISORDER IN ONE EVALUATION, N = 38), AND (3) PERSISTENT GROUP (ANXIETY DISORDER AT BOTH TIME POINTS, N = 20). WE ASSESSED RELATIVE MEAN TL BY REAL-TIME QUANTITATIVE PCR AND DNA METHYLATION BY INFINIUM HUMANMETHYLATION450 BEADCHIP. WE CALCULATED AA USING THE HORVATH AGE ESTIMATION ALGORITHM AND ANALYZED DIFFERENCES AMONG GROUPS USING GENERALIZED LINEAR MIXED MODELS. THE PERSISTENT GROUP OF ANXIETY DISORDER DID NOT CHANGE TL OVER TIME (P = 0.495). THE VARIABLE GROUP HAD HIGHER BASELINE TL (P = 0.003) BUT NO ACCELERATED TL EROSION IN COMPARISON TO THE NON-ANXIETY CONTROL GROUP (P = 0.053). FURTHERMORE, THERE WERE NO DIFFERENCES IN AA AMONG GROUPS OVER TIME. OUR FINDINGS SUGGEST THAT ADOLESCENTS WITH CHRONIC ANXIETY DID NOT CHANGE TELOMERE LENGTH OVER TIME, WHICH COULD BE RELATED TO A DELAY IN NEURONAL DEVELOPMENT IN THIS PERIOD OF LIFE. 2021 12 3652 31 INDIVIDUAL DNA METHYLATION PATTERN SHIFTS IN NANOPARTICLES-EXPOSED WORKERS ANALYZED IN FOUR CONSECUTIVE YEARS. A DNA METHYLATION PATTERN REPRESENTS AN ORIGINAL PLAN OF THE FUNCTION SETTINGS OF INDIVIDUAL CELLS AND TISSUES. THE BASIC STRATEGIES OF ITS DEVELOPMENT AND CHANGES DURING THE HUMAN LIFETIME ARE KNOWN, BUT THE DETAILS RELATED TO ITS MODIFICATION OVER THE YEARS ON AN INDIVIDUAL BASIS HAVE NOT YET BEEN STUDIED. MOREOVER, CURRENT EVIDENCE SHOWS THAT ENVIRONMENTAL EXPOSURE COULD GENERATE CHANGES IN DNA METHYLATION SETTINGS AND, SUBSEQUENTLY, THE FUNCTION OF GENES. IN THIS STUDY, WE ANALYZED THE EFFECT OF CHRONIC EXPOSURE TO NANOPARTICLES (NP) IN OCCUPATIONALLY EXPOSED WORKERS REPEATEDLY SAMPLED IN FOUR CONSECUTIVE YEARS (2016-2019). A DETAILED METHYLATION PATTERN ANALYSIS OF 14 PERSONS (10 EXPOSED AND 4 CONTROLS) WAS PERFORMED ON AN INDIVIDUAL BASIS. A MICROARRAY-BASED APPROACH USING CHIPS, ALLOWING THE ASSESSMENT OF MORE THAN 850 K CPG LOCI, WAS USED. INDIVIDUAL DNA METHYLATION PATTERNS WERE COMPARED BY PRINCIPAL COMPONENT ANALYSIS (PCA). THE RESULTS SHOW THE SHIFT IN DNA METHYLATION PATTERNS IN INDIVIDUAL YEARS IN ALL THE EXPOSED AND CONTROL SUBJECTS. THE OVERALL RANGE OF DIFFERENCES VARIED BETWEEN THE YEARS IN INDIVIDUAL PERSONS. THE DIFFERENCES BETWEEN THE FIRST AND LAST YEAR OF EXAMINATION (A THREE-YEAR TIME PERIOD) SEEM TO BE CONSISTENTLY GREATER IN THE NP-EXPOSED SUBJECTS IN COMPARISON WITH THE CONTROLS. THE SELECTED 14 MOST DIFFERENTLY METHYLATED CG LOCI WERE RELATIVELY STABLE IN THE CHRONICALLY EXPOSED SUBJECTS. IN SUMMARY, THE SPECIFIC TYPE OF LONG-TERM EXPOSURE CAN CONTRIBUTE TO THE FIXING OF RELEVANT EPIGENETIC CHANGES RELATED TO A SPECIFIC ENVIRONMENT AS, E.G., NP INHALATION. 2021 13 1503 28 DNA METHYLATION AND GENE EXPRESSION DIFFERENCES IN CHILDREN CONCEIVED IN VITRO OR IN VIVO. EPIDEMIOLOGICAL DATA INDICATE THAT CHILDREN CONCEIVED IN VITRO HAVE A GREATER RELATIVE RISK OF LOW BIRTH-WEIGHT, MAJOR AND MINOR BIRTH DEFECTS, AND RARE DISORDERS INVOLVING IMPRINTED GENES, SUGGESTING THAT EPIGENETIC CHANGES MAY BE ASSOCIATED WITH ASSISTED REPRODUCTION. WE EXAMINED DNA METHYLATION AT MORE THAN 700 GENES (1536 CPG SITES) IN PLACENTA AND CORD BLOOD AND MEASURED GENE EXPRESSION LEVELS OF A SUBSET OF GENES THAT DIFFERED IN METHYLATION LEVELS BETWEEN CHILDREN CONCEIVED IN VITRO VERSUS IN VIVO. OUR RESULTS SUGGEST THAT IN VITRO CONCEPTION IS ASSOCIATED WITH LOWER MEAN METHYLATION AT CPG SITES IN PLACENTA AND HIGHER MEAN METHYLATION AT CPG SITES IN CORD BLOOD. WE ALSO FIND THAT IN VITRO CONCEPTION-ASSOCIATED DNA METHYLATION DIFFERENCES ARE ASSOCIATED WITH GENE EXPRESSION DIFFERENCES AT BOTH IMPRINTED AND NON-IMPRINTED GENES. THE RANGE OF INTER-INDIVIDUAL VARIATION IN GENE EXPRESSION OF THE IN VITRO AND IN VIVO GROUPS OVERLAPS SUBSTANTIALLY BUT SOME INDIVIDUALS FROM THE IN VITRO GROUP DIFFER FROM THE IN VIVO GROUP MEAN BY MORE THAN TWO STANDARD DEVIATIONS. SEVERAL OF THE GENES WHOSE EXPRESSION DIFFERS BETWEEN THE TWO GROUPS HAVE BEEN IMPLICATED IN CHRONIC METABOLIC DISORDERS, SUCH AS OBESITY AND TYPE II DIABETES. THESE FINDINGS SUGGEST THAT THERE MAY BE EPIGENETIC DIFFERENCES IN THE GAMETES OR EARLY EMBRYOS DERIVED FROM COUPLES UNDERGOING TREATMENT FOR INFERTILITY. ALTERNATIVELY, ASSISTED REPRODUCTION TECHNOLOGY MAY HAVE AN EFFECT ON GLOBAL PATTERNS OF DNA METHYLATION AND GENE EXPRESSION. IN EITHER CASE, THESE DIFFERENCES OR CHANGES MAY AFFECT LONG-TERM PATTERNS OF GENE EXPRESSION. 2009 14 1810 34 EFFECTS OF ANTIPSYCHOTICS ON THE BDNF IN SCHIZOPHRENIA. BRAIN-DERIVED NEUROTROPIC FACTOR (BDNF) IS INVOLVED IN THE DEVELOPMENT OF THE BRAIN, AND LIKELY INFLUENCES THE NEUROPLASTICITY IN SCHIZOPHRENIA. BDNF IS ALSO BELIEVED TO INTERACT WITH OTHER NEUROTRANSMITTER SYSTEMS IMPLICATED IN SCHIZOPHRENIA, SUCH AS DOPAMINE, GLUTAMATE, SEROTONIN AND GABA. THEREFORE, BDNF IS A CANDIDATE GENE FOR SCHIZOPHRENIA. IN PAST DECADES, THE BLOOD (SERUM OR PLASMA) BDNF PROTEIN LEVELS AND BDNF GENE ALLELES AND GENOTYPES TO THE CLINICAL FEATURES OF SCHIZOPHRENIA, SUCH AS AGE OF ONSET, CLINICAL SUBTYPES, SYMPTOM SEVERITY, AND DRUG RESPONSE, HAVE BEEN EVALUATED AMONG DIFFERENT POPULATIONS. HOWEVER, THE RESULTS ARE STILL INCONSISTENT. FURTHER, DIFFERENT DRUGS HAVE BEEN REPORTED TO HAVE DIFFERENT EFFECTS ON BDNF PROTEIN LEVELS. A CROSS-SECTIONAL SURVEY REVEALED THAT SERUM BDNF LEVELS IN CHRONIC SCHIZOPHRENIC PATIENTS TREATED WITH CLOZAPINE EXCEEDED THOSE OF PATIENTS TREATED WITH RISPERIDONE OR WITH TYPICAL ANTIPSYCHOTICS. IN RECENT TIMES, BDNF EPIGENETIC STUDIES HAVE ALSO BEEN CONDUCTED IN CLINICAL STUDIES OF SCHIZOPHRENIA TO ADDRESS THE QUESTION OF WHY PATIENTS WITH THE SAME GENE GENOTYPE AND ALLELES HAVE DIFFERENT CLINICAL PRESENTATIONS. IN ADDITION, THE EFFECTS OF DIFFERENT ANTIPSYCHOTIC DRUGS ON GENE METHYLATION AND PROTEIN ACETYLATION HAVE ALSO BEEN REPORTED. IN CONCLUSION, MORE DATA ARE NEEDED REGARDING BDNF IN THE BRAIN AND IN PERIPHERAL BLOOD, INCLUDING PROTEIN LEVELS, SINGLE NUCLEOTIDE POLYMORPHISMS, EPIGENETIC REGULATION, AND CLINICAL DATA IN ORDER TO UNDERSTAND THE ROLE OF BDNF IN SCHIZOPHRENIA. 2013 15 2215 33 EPIGENETIC MODIFICATIONS FOLLOWING NOXIOUS STIMULI IN INFANTS. PURPOSE: TO RECRUIT HEALTHY FULL- AND PRETERM INFANTS INTO GENETIC RESEARCH AND DETERMINE THE EFFECTIVENESS OF A NONINVASIVE DNA SAMPLING TECHNIQUE FOR COMPARING EPIGENETIC MODIFICATIONS. BACKGROUND: NOXIOUS STIMULI DURING A VULNERABLE PERIOD OF INFANT NEURONAL PLASTICITY MAY TRIGGER LONG-TERM EPIGENETIC CHANGES AFFECTING NEURODEVELOPMENT, PAIN MODULATION, AND REACTIVITY. RECOGNIZING EPIGENETIC PAIN FINDINGS IS PROBLEMATIC BECAUSE PARENTS ARE RELUCTANT TO ENROLL NEWBORNS INTO GENETIC RESEARCH. METHODS: DESIGN: WITHIN-SUBJECT CHANGE OVER TIME CANDIDATE-GENE DNA METHYLATION ASSOCIATION STUDY. SETTING/ SAMPLE: URBAN TEACHING HOSPITAL'S NEONATAL INTENSIVE CARE UNIT AND NEWBORN NURSERY. CONVENIENCE SAMPLE OF HEALTHY FULL- (>37 WEEKS, N = 6) AND PRETERM (<37 WEEKS, N = 6) INFANTS. PROCEDURE: PARENTS PARTICIPATED IN A GENETIC PRESENTATION PRIOR TO INFORMED CONSENT. INFANT BUCCAL SALIVA WAS COLLECTED AFTER ADMISSION TO THE UNIT AND PRIOR TO DISCHARGE. ANALYSIS: THE METHYLATION PATTERN AT THE 5' END OF MICRO-OPIOID RECEPTOR GENE ( OPRM1) WAS EXAMINED. DNA WAS TREATED WITH BISULFITE TO CONVERT ALL CYTOSINES TO URACIL RESIDUES, LEAVING METHYLATED CYTOSINES UNCHANGED. SEQUENCING OF UNTREATED AND BISULFITE-CONVERTED DNA WAS CARRIED OUT. THE SEQUENCES OF UNCONVERTED AND BISULFITE-CONVERTED DNA WERE ALIGNED WITH CLUSTALW, FIDELITY OF THE POLYMERASE CHAIN REACTION AND THE SEQUENCING REACTION EVALUATED, AND THE METHYLATION PATTERN IDENTIFIED. RESULTS: RECRUITMENT AND ASSESSMENT OF A NONINVASIVE DNA SAMPLING TECHNIQUE FOR COMPARING EPIGENETIC MODIFICATIONS WERE SUCCESSFUL; HOWEVER, INFANT STRESS DID NOT PRODUCE A CHANGE IN OPRM1 METHYLATION EXPRESSION. RELEVANCE: THIS STUDY ESTABLISHED THE FEASIBILITY OF RECRUITING HEALTHY FULL-TERM INFANTS INTO GENETIC RESEARCH AND THE EFFECTIVENESS OF NONINVASIVE DNA SAMPLING FOR COMPARING EPIGENETIC MODIFICATION IN INFANTS. 2018 16 2079 30 EPIGENETIC DNA METHYLATION CHANGES ASSOCIATED WITH HEADACHE CHRONIFICATION: A RETROSPECTIVE CASE-CONTROL STUDY. BACKGROUND THE BIOLOGICAL MECHANISMS OF HEADACHE CHRONIFICATION ARE POORLY UNDERSTOOD. WE AIMED TO IDENTIFY CHANGES IN DNA METHYLATION ASSOCIATED WITH THE TRANSFORMATION FROM EPISODIC TO CHRONIC HEADACHE. METHODS PARTICIPANTS WERE RECRUITED FROM THE POPULATION-BASED NORWEGIAN HUNT STUDY. THIRTY-SIX FEMALE HEADACHE PATIENTS WHO TRANSFORMED FROM EPISODIC TO CHRONIC HEADACHE BETWEEN BASELINE AND FOLLOW-UP 11 YEARS LATER WERE MATCHED AGAINST 35 CONTROLS WITH EPISODIC HEADACHE. DNA METHYLATION WAS QUANTIFIED AT 485,000 CPG SITES, AND CHANGES IN METHYLATION LEVEL AT THESE SITES WERE COMPARED BETWEEN CASES AND CONTROLS BY LINEAR REGRESSION ANALYSIS. DATA WERE ANALYZED IN TWO STAGES (STAGES 1 AND 2) AND IN A COMBINED META-ANALYSIS. RESULTS NONE OF THE TOP 20 CPG SITES IDENTIFIED IN STAGE 1 REPLICATED IN STAGE 2 AFTER MULTIPLE TESTING CORRECTION. IN THE COMBINED META-ANALYSIS THE STRONGEST ASSOCIATED CPG SITES WERE RELATED TO SH2D5 AND NPTX2, TWO BRAIN-EXPRESSED GENES INVOLVED IN THE REGULATION OF SYNAPTIC PLASTICITY. FUNCTIONAL ENRICHMENT ANALYSIS POINTED TO PROCESSES INCLUDING CALCIUM ION BINDING AND ESTROGEN RECEPTOR PATHWAYS. CONCLUSION IN THIS FIRST GENOME-WIDE STUDY OF DNA METHYLATION IN HEADACHE CHRONIFICATION SEVERAL POTENTIALLY IMPLICATED LOCI AND PROCESSES WERE IDENTIFIED. THE STUDY EXEMPLIFIES THE USE OF PROSPECTIVELY COLLECTED POPULATION COHORTS TO SEARCH FOR EPIGENETIC MECHANISMS OF DISEASE. 2018 17 3136 32 GLOBAL DNA METHYLATION LEVELS IN WHITE BLOOD CELLS OF PATIENTS WITH CHRONIC HEROIN USE DISORDER. A PROSPECTIVE STUDY. BACKGROUND: INCREASING SCIENTIFIC EVIDENCE SHOWS THE SIGNIFICANT ROLE OF EPIGENETIC MECHANISMS IN DRUG USE DISORDER, ABSTINENCE AND RELAPSE. STUDIES ON HUMAN SUBJECTS ARE LIMITED COMPARED TO THOSE ON ANIMALS, FOR VARIOUS REASONS SUCH AS POLY-SUBSTANCE ABUSE, HIGH DROP-OUT RATE AND TECHNICAL DIFFICULTIES. OBJECTIVES: OUR GOAL WAS TO EVALUATE WHETHER A MONITORED ABSTINENCE PERIOD OF 21 DAYS COULD INDUCE CHANGES IN GLOBAL DNA METHYLATION IN CHRONIC HEROIN USERS. METHOD: IN THE CURRENT STUDY, WE PRESENT DATA ON GLOBAL DNA METHYLATION ON A SET OF 18 MALE PATIENTS WITH CHRONIC HEROIN USE DISORDER, CAREFULLY SELECTED BASED ON INCLUSION AND EXCLUSION CRITERIA, WHO WERE HOSPITALIZED AND CLOSELY MONITORED DURING A 21-DAY DETOXIFICATION PROGRAM, ONE OF THE FEW WHERE NO OPIOID AGONIST IS ADMINISTERED. THE PARTICIPANTS WERE SAMPLED TWICE, ONCE UPON ENROLMENT TO THE PROGRAM AND ONCE UPON COMPLETION. RESULTS: ACCORDING TO OUR RESULTS, NO DIFFERENCE IN GLOBAL DNA METHYLATION WAS DETECTED BETWEEN SAMPLES COLLECTED UPON ENROLMENT AND SAMPLES COLLECTED UPON COMPLETION OF THE PROGRAM. CONCLUSION: THE FINDINGS OF THIS STUDY DO NOT RULE OUT THE POSSIBILITY THAT THE 21-DAY ABSTINENCE PERIOD WAS NOT LONG ENOUGH TO OBSERVE CHANGES IN GLOBAL DNA METHYLATION, OR THAT ABSTINENCE INDUCED SITE-SPECIFIC METHYLATION CHANGES (BUT NOT GLOBAL CHANGES), THAT CERTAINLY MERIT FURTHER EVALUATION. 2021 18 6418 37 THE TEMPORAL EXPRESSION OF CIRCULATING MICRORNAS AFTER ACUTE EXPERIMENTAL PAIN IN HUMANS. BACKGROUND: MICRORNAS (MIRNAS) CAN MODULATE SEVERAL BIOLOGICAL SYSTEMS, INCLUDING THE PAIN SYSTEM. THIS STUDY AIMED TO EVALUATE THE TEMPORAL EXPRESSION OF CIRCULATING MIRNAS IN THE PLASMA OF HEALTHY VOLUNTEERS AS A MARKER FOR EPIGENETIC CHANGES BEFORE AND AFTER AN ACUTE, EXPERIMENTAL, PAIN PROVOCATION BY INTRAMUSCULAR HYPERTONIC SALINE INJECTION. METHODS: TWENTY VOLUNTEERS WERE RANDOMLY ALLOCATED INTO TWO GROUPS AND RECEIVED EITHER HYPERTONIC (PAIN) OR ISOTONIC (CONTROL) SALINE INJECTION IN THE FIRST DORSAL INTEROSSEOUS MUSCLE OF THEIR DOMINANT HAND. PAIN INTENSITY WAS CONTINUOUSLY RECORDED FOR 20 MINUTES AFTER INJECTION ON A VAS SCALE FROM 0 TO 100 (0 INDICATES NO PAIN AND 100 THE WORST IMAGINABLE PAIN). BLOOD SAMPLES WERE TAKEN AT BASELINE, 30 MINUTES, 3 HOURS, AND 24 HOURS POST-INJECTION, AND PLASMA WAS SEPARATED. MIRNA EXTRACTS WERE USED FOR RNA SEQUENCING WITH THE ILLUMINA NEXTSEQ PLATFORM. MIRNA TRANSCRIPTS WERE COMPARED BETWEEN THE PAIN AND THE NO-PAIN, CONTROL GROUP AT EVERY TIME POINT. SIGNIFICANT DIFFERENCES WERE CONSIDERED WHEN FOLDS WERE >2 AND THE FALSE DISCOVERY RATE WAS P < 0.05. RESULTS: AFTER 30 MINUTES, 4 MIRNAS WERE SIGNIFICANTLY ALTERED IN THE PAIN GROUP COMPARED TO CONTROLS, WHICH INCREASED TO 24 AFTER 3 HOURS AND TO 42 AFTER 24 HOURS FROM BASELINE (P < 0.0001). TWO MIRNAS WERE CONSISTENTLY UPREGULATED THROUGHOUT THE EXPERIMENT. ENRICHMENT ANALYSIS SHOWED SIGNIFICANT MIRNAS INVOLVED IN BRAIN PERCEPTION OF PAIN, BRAIN SIGNALLING AND RESPONSE TO STIMULI. CONCLUSIONS: THIS EXPLORATORY STUDY IS THE FIRST TO REPORT ON THE TEMPORAL EXPRESSION OF CIRCULATING MIRNAS AFTER AN ACUTE, HUMAN EXPERIMENTAL MUSCLE PAIN MODEL. SIGNIFICANCE: THIS EXPLORATORY STUDY EVALUATED THE TEMPORAL PROFILE OF CIRCULATING MIRNAS IN THE PLASMA OF HEALTHY SUBJECTS AFTER ACUTE EXPERIMENTAL PAIN. SEVERAL MIRNAS WERE ALTERED IN SUBJECTS AT THE TIMES OF FOLLOW-UP AFTER THE ACUTE PAIN MODEL WHEN COMPARED TO CONTROLS. MIRNAS PREVIOUSLY ASSOCIATED WITH PAIN PROCESSES WERE ALTERED IN THE PAIN GROUP. OUR RESULTS, BY SHOWING THE FAST AND PROLONGED MODIFICATIONS OF MIRNA ELICITED BY THE ACUTE EXPERIMENTAL PAIN MODEL, ADD NEW PERSPECTIVES TO THE TOPIC OF EPIGENETICS AND PAIN. 2023 19 1345 36 DETECTION OF DIFFERENTIALLY METHYLATED REGIONS USING BAYES FACTOR FOR ORDINAL GROUP RESPONSES. RESEARCHERS IN GENOMICS ARE INCREASINGLY INTERESTED IN EPIGENETIC FACTORS SUCH AS DNA METHYLATION, BECAUSE THEY PLAY AN IMPORTANT ROLE IN REGULATING GENE EXPRESSION WITHOUT CHANGES IN THE DNA SEQUENCE. THERE HAVE BEEN SIGNIFICANT ADVANCES IN DEVELOPING STATISTICAL METHODS TO DETECT DIFFERENTIALLY METHYLATED REGIONS (DMRS) ASSOCIATED WITH BINARY DISEASE STATUS. MOST OF THESE METHODS ARE BEING DEVELOPED FOR DETECTING DIFFERENTIAL METHYLATION RATES BETWEEN CASES AND CONTROLS. WE CONSIDER MULTIPLE SEVERITY LEVELS OF DISEASE, AND DEVELOP A BAYESIAN STATISTICAL METHOD TO DETECT THE REGION WITH INCREASING (OR DECREASING) METHYLATION RATES AS THE DISEASE SEVERITY INCREASES. PATIENTS ARE CLASSIFIED INTO MORE THAN TWO GROUPS, BASED ON THE DISEASE SEVERITY (E.G., STAGES OF CANCER), AND DMRS ARE DETECTED BY USING MOVING WINDOWS ALONG THE GENOME. WITHIN EACH WINDOW, THE BAYES FACTOR IS CALCULATED TO TEST THE HYPOTHESIS OF MONOTONIC INCREASE IN METHYLATION RATES CORRESPONDING TO SEVERITY OF THE DISEASE VERSUS NO DIFFERENCE. A MIXED-EFFECT MODEL IS USED TO INCORPORATE THE CORRELATION OF METHYLATION RATES OF NEARBY CPG SITES IN THE REGION. RESULTS FROM EXTENSIVE SIMULATION INDICATE THAT OUR PROPOSED METHOD IS STATISTICALLY VALID AND REASONABLY POWERFUL. WE DEMONSTRATE OUR APPROACH ON A BISULFITE SEQUENCING DATASET FROM A CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) STUDY. 2019 20 1497 29 DNA METHYLATION AGE IS ACCELERATED IN ALCOHOL DEPENDENCE. ALCOHOL DEPENDENCE (ALC) IS A CHRONIC, RELAPSING DISORDER THAT INCREASES THE BURDEN OF CHRONIC DISEASE AND SIGNIFICANTLY CONTRIBUTES TO NUMEROUS PREMATURE DEATHS EACH YEAR. PREVIOUS RESEARCH SUGGESTS THAT CHRONIC, HEAVY ALCOHOL CONSUMPTION IS ASSOCIATED WITH DIFFERENTIAL DNA METHYLATION PATTERNS. IN ADDITION, DNA METHYLATION LEVELS AT CERTAIN CPG SITES HAVE BEEN CORRELATED WITH AGE. WE USED AN EPIGENETIC CLOCK TO INVESTIGATE THE POTENTIAL ROLE OF EXCESSIVE ALCOHOL CONSUMPTION IN EPIGENETIC AGING. WE EXPLORED THIS QUESTION IN FIVE INDEPENDENT COHORTS, INCLUDING DNA METHYLATION DATA DERIVED FROM DATASETS FROM BLOOD (N = 129, N = 329), LIVER (N = 92, N = 49), AND POSTMORTEM PREFRONTAL CORTEX (N = 46). ONE BLOOD DATASET AND ONE LIVER TISSUE DATASET OF INDIVIDUALS WITH ALC EXHIBITED POSITIVE AGE ACCELERATION (P < 0.0001 AND P = 0.0069, RESPECTIVELY), WHEREAS THE OTHER BLOOD AND LIVER TISSUE DATASETS BOTH EXHIBITED TRENDS OF POSITIVE AGE ACCELERATION THAT WERE NOT SIGNIFICANT (P = 0.83 AND P = 0.57, RESPECTIVELY). PREFRONTAL CORTEX TISSUE EXHIBITED A TREND OF NEGATIVE AGE ACCELERATION (P = 0.19). THESE RESULTS SUGGEST THAT EXCESSIVE ALCOHOL CONSUMPTION MAY BE ASSOCIATED WITH EPIGENETIC AGING IN A TISSUE-SPECIFIC MANNER AND WARRANTS FURTHER INVESTIGATION USING MULTIPLE TISSUE SAMPLES FROM THE SAME INDIVIDUALS. 2018