1 4718 103 NON-TYPEABLE HAEMOPHILUS INFLUENZAE ISOLATES FROM PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE CONTAIN NEW PHASE-VARIABLE MODA METHYLTRANSFERASE ALLELES CONTROLLING PHASEVARIONS. PHASEVARIONS (PHASE-VARIABLE REGULONS) ARE EMERGING AS AN IMPORTANT AREA OF BACTERIAL GENE REGULATION. MANY BACTERIAL PATHOGENS CONTAIN PHASEVARIONS, WITH GENE EXPRESSION CONTROLLED BY THE PHASE-VARIABLE EXPRESSION OF DNA METHYLTRANSFERASES VIA EPIGENETIC MECHANISMS. NON-TYPEABLE HAEMOPHILUS INFLUENZAE (NTHI) CONTAINS THE PHASE-VARIABLE METHYLTRANSFERASE MODA, OF WHICH MULTIPLE ALLELIC VARIANTS EXIST (MODA1-21). WE HAVE PREVIOUSLY DEMONSTRATED 5 OF 21 THESE MODA ALLELES ARE OVERREPRESENTED IN NTHI STRAINS ISOLATED FROM CHILDREN WITH MIDDLE EAR INFECTIONS. IN THIS STUDY WE INVESTIGATED THE MODA ALLELE DISTRIBUTION IN NTHI STRAINS ISOLATED FROM PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE, COPD. WE DEMONSTRATE THAT THE DISTRIBUTION OF MODA ALLELES IN A LARGE PANEL OF COPD ISOLATES IS DIFFERENT TO THE DISTRIBUTION SEEN IN MIDDLE EAR INFECTIONS, SUGGESTING DIFFERENT MODA ALLELES MAY PROVIDE DISTINCT ADVANTAGES IN THE DIFFERING NICHES OF THE MIDDLE EAR AND COPD AIRWAYS. WE ALSO IDENTIFIED TWO NEW PHASE-VARIABLE MODA ALLELES - MODA15 AND MODA18 - AND DEMONSTRATE THAT THESE ALLELES METHYLATE DISTINCT DNA SEQUENCES AND CONTROL UNIQUE PHASEVARIONS. THE MODA15 AND MODA18 ALLELES HAVE ONLY BEEN OBSERVED IN COPD ISOLATES, INDICATING THAT THESE TWO ALLELES MAY BE MARKERS FOR ISOLATES LIKELY TO CAUSE EXACERBATIONS OF COPD. 2019 2 2684 30 EVALUATION OF X CHROMOSOME INACTIVATION WITH RESPECT TO HLA GENETIC SUSCEPTIBILITY IN RHEUMATOID ARTHRITIS AND SYSTEMIC SCLEROSIS. BACKGROUND: AUTOIMMUNE DISEASES, INCLUDING RHEUMATOID ARTHRITIS (RA) AND SYSTEMIC SCLEROSIS (SSC) ARE CHARACTERIZED BY A STRONG GENETIC SUSCEPTIBILITY FROM THE HUMAN LEUCOCYTE ANTIGEN (HLA) LOCUS. ADDITIONALLY, DISORDERS OF EPIGENETIC PROCESSES, IN PARTICULAR NON-RANDOM X CHROMOSOME INACTIVATION (XCI), HAVE BEEN REPORTED IN MANY FEMALE-PREDOMINANT AUTOIMMUNE DISEASES. HERE WE TEST THE HYPOTHESIS THAT WOMEN WITH RA OR SSC WHO ARE STRONGLY GENETICALLY PREDISPOSED ARE LESS SUSCEPTIBLE TO XCI BIAS. METHODS: USING METHYLATION SENSITIVE GENOTYPING OF THE ANDROGEN RECEPTOR (AR) GENE, XCI PROFILES WERE PERFORMED IN PERIPHERAL BLOOD MONONUCLEAR CELLS FROM 161 WOMEN WITH RA, 96 WOMEN WITH SSC AND 100 HEALTHY WOMEN. HLA-DRB1 AND DQB1 WERE GENOTYPED. PRESENCE OF SPECIFIC AUTOANTIBODIES WAS DOCUMENTED FOR PATIENTS. XCI SKEWING WAS DEFINED AS HAVING A RATIO >/= 80:20 OF CELLS INACTIVATING THE SAME X CHROMOSOME. RESULTS: 110 WOMEN WITH RA, 68 WOMEN WITH SSC, AND 69 CONTROLS WERE INFORMATIVE FOR THE AR POLYMORPHISM. AMONG THEM 40.9% OF RA PATIENTS AND 36.8% OF SSC PATIENTS HAD SKEWED XCI COMPARED TO 17.4% OF HEALTHY WOMEN (P = 0.002 AND 0.018, RESPECTIVELY). PRESENCE OF RA-SUSCEPTIBILITY ALLELES CODING FOR THE "SHARED EPITOPE" CORRELATED WITH HIGHER SKEWING AMONG RA PATIENTS (P = 0.002) AND SUCH CORRELATION WAS NOT OBSERVED IN OTHER WOMEN, HEALTHY OR WITH SSC. PRESENCE OF SSC-SUSCEPTIBILITY ALLELES DID NOT CORRELATE WITH XCI PATTERNS AMONG SSC PATIENTS. CONCLUSION: DATA DEMONSTRATE XCI SKEWING IN BOTH RA AND SSC COMPARED TO HEALTHY WOMEN. UNEXPECTEDLY, SKEWED XCI OCCURS MORE OFTEN IN WOMEN WITH RA CARRYING THE SHARED EPITOPE, WHICH USUALLY REFLECTS SEVERE DISEASE. THIS REINFORCES THE VIEW THAT LOSS OF MOSAICISM IN PERIPHERAL BLOOD MAY BE A CONSEQUENCE OF CHRONIC AUTOIMMUNITY. 2016 3 163 31 ABL1 METHYLATION IS A DISTINCT MOLECULAR EVENT ASSOCIATED WITH CLONAL EVOLUTION OF CHRONIC MYELOID LEUKEMIA. METHYLATION OF THE PROXIMAL PROMOTER OF THE ABL1 ONCOGENE IS A COMMON EPIGENETIC ALTERATION ASSOCIATED WITH CLINICAL PROGRESSION OF CHRONIC MYELOID LEUKEMIA (CML). IN THIS STUDY WE QUERIED WHETHER BOTH THE PH'-ASSOCIATED AND NORMAL ABL1 ALLELES UNDERGO METHYLATION; WHAT MAY BE THE PROPORTION OF HEMATOPOIETIC PROGENITORS BEARING METHYLATED ABL1 PROMOTERS IN CHRONIC VERSUS ACUTE PHASE DISEASE; WHETHER METHYLATION AFFECTS THE PROMOTER UNIFORMLY OR IN PATCHES WITH DISCRETE CLINICAL RELEVANCE; AND, FINALLY, WHETHER METHYLATION OF ABL1 REFLECTS A GENERALIZED PROCESS OR IS GENE-SPECIFIC. TO ADDRESS THESE ISSUES, WE ADAPTED THE TECHNIQUES OF METHYLATION-SPECIFIC PCR AND BISULFITE-SEQUENCING TO STUDY THE REGULATORY REGIONS OF ABL1 AND OTHER GENES WITH A ROLE IN DNA REPAIR OR GENOTOXIC STRESS RESPONSE. IN CELL LINES ESTABLISHED FROM CML BLAST CRISIS, WHICH ONLY CARRY A SINGLE ABL1 ALLELE NESTED WITHIN THE BCR-ABL FUSION GENE, ABL1 PROMOTERS WERE UNIVERSALLY METHYLATED. BY CONTRAST, IN CLINICAL SAMPLES FROM PATIENTS AT ADVANCED STAGES OF DISEASE, BOTH METHYLATED AND UNMETHYLATED PROMOTER ALLELES WERE DETECTABLE. TO DISTINGUISH BETWEEN ALLELE-SPECIFIC METHYLATION AND A MIXED CELL POPULATION PATTERN, WE STUDIED THE METHYLATION STATUS OF ABL1 IN COLONIES DERIVED FROM SINGLE HEMATOPOIETIC PROGENITORS. OUR RESULTS SHOWED THAT BOTH METHYLATED AND UNMETHYLATED PROMOTER ALLELES COEXISTED IN THE SAME COLONY. FURTHERMORE, ABL1 METHYLATION WAS NOTED IN THE VAST MAJORITY OF COLONIES FROM BLAST CRISIS, BUT NOT CHRONIC-PHASE CML. BOTH CELL LINES AND CLINICAL SAMPLES FROM ACUTE-PHASE CML SHOWED NEARLY UNIFORM HYPERMETHYLATION ALONG THE PROMOTER REGION. FINALLY, WE SHOWED THAT ABL1 METHYLATION DOES NOT REFLECT A GENERALIZED PROCESS AND MAY BE UNIQUE AMONG DNA REPAIR/GENOTOXIC STRESS RESPONSE GENES. OUR DATA SUGGEST THAT SPECIFIC METHYLATION OF THE PH'-ASSOCIATED ABL1 ALLELE ACCOMPANIES CLONAL EVOLUTION IN CML. 1999 4 6366 29 THE ROLE OF METHYLATION IN CML. METHYLATION OF THE PROXIMAL PROMOTER OF THE ABL1 ONCOGENE IS COMMON EPIGENETIC ALTERATION ASSOCIATED WITH CLINICAL PROGRESSION OF CHRONIC MYELOID LEUKEMIA (CML). IN PRESENTED STUDY WE QUERIED WHETHER BOTH THE PH'-ASSOCIATED AND NORMAL ABL1 ALLELES UNDERGO METHYLATION; WHAT MAY BE THE PROPORTION OF HEMATOPOIETIC PROGENITORS BEARING METHYLATED ABL1 PROMOTERS IN CHRONIC VERSUS ACUTE PHASE DISEASE; WHETHER METHYLATION AFFECTS THE PROMOTER UNIFORMLY OR IN PATCHES WITH DISCRETE CLINICAL RELEVANCE; AND, FINALLY WHETHER METHYLATION OF ABL1 REFLECTS A GENERALIZED PROCESS OR IS GENE-SPECIFIC. TO ADDRESS THESE ISSUES, THE TECHNIQUE OF METHYLATION-SPECIFIC PCR AND BISULFITE-SEQUENCING WAS ADAPTED TO STUDY THE REGULATORY REGIONS OF ABL1 AND OTHER GENES. IN CELL LINES ESTABLISHED FROM CML BLAST CRISIS, WHICH ONLY CARRY A SINGLE ABL1 ALLELE NESTED WITHIN THE BCR-ABL FUSION GENE, ABL1 PROMOTERS WERE UNIVERSALLY METHYLATED. IN CLINICAL SAMPLES FROM PATIENTS AT ADVANCED STAGES OF THE DISEASE, BOTH METHYLATED AND UNMETHYLATED PROMOTER ALLELES WERE DETECTABLE. IN COLONIES DERIVED FROM SINGLE HEMATOPOIETIC PROGENITORS METHYLATED AND UNMETHYLATED PROMOTER ALLELES WERE REVEALED AS WELL. ABL1 METHYLATION WAS WAS NOTED IN THE VAST MAJORITY OF COLONIES FROM BLAST CRISIS, BUT NOT CHRONIC-PHASE CML. IT WAS SHOWN FINALLY THAT ABL1 METHYLATION DOES NOT REFLECT A GENERALIZED PROCESS AND MAY BE UNIQUE AMONG DNA REPAIR/GENOTOXIC STRESS RESPONSE GENES. THESE DATA SUGGEST THAT SPECIFIC METHYLATION OF THE PH'-ASSOCIATED ABL1 ALLELE ACCOMPANIES CLONAL EVOLUTION IN CML. 2000 5 5700 32 SINGLE NUCLEOTIDE POLYMORPHISM IN DNMT3B PROMOTER AND THE RISK FOR IDIOPATHIC THROMBOCYTOPENIC PURPURA IN CHINESE POPULATION. OBJECTIVE: EPIGENETIC CHANGES IN GENE EXPRESSION, INCLUDING DNA METHYLATION AND HISTONE MODIFICATIONS, MIGHT CONTRIBUTE TO AUTOIMMUNITY. DNA METHYLATION IS MEDIATED BY A FAMILY OF DNA METHYLTRANSFERASES. POLYMORPHISMS OF THE DNA METHYLTRANSFERASE 3B (DNMT3B) GENE MAY INFLUENCE DNMT3B ACTIVITY ON DNA METHYLATION, THEREBY MODULATING THE SUSCEPTIBILITY TO SOME DISEASES. THE PURPOSE OF THIS STUDY WAS TO INVESTIGATE THE ASSOCIATION BETWEEN THE SINGLE NUCLEOTIDE POLYMORPHISM (SNP) IN PROMOTER OF THE DNMT3B GENE AND THE RISK FOR DEVELOPMENT OF IDIOPATHIC THROMBOCYTOPENIC PURPURA (ITP). METHODS: IN THIS HOSPITAL-BASED CASE-CONTROL STUDY, THE DNMT3B SNP WAS GENOTYPED IN 201 PATIENTS WITH ITP AND 136 HEALTHY CONTROLS BY POLYMERASE CHAIN REACTION-RESTRICTION FRAGMENT LENGTH POLYMORPHISM. RESULTS: THE C/C GENOTYPE WAS NOT DETECTED IN BOTH THE PATIENTS WITH ITP AND THE CONTROLS. IN THE CONTROLS, THE FREQUENCIES OF T/T AND C/T GENOTYPES AND T AND C ALLELES WERE 97.8%, 2.2%, 98.9%, AND 1.1%, RESPECTIVELY. THERE WAS NO SIGNIFICANT DIFFERENCE IN GENOTYPE AND ALLELE DISTRIBUTION BETWEEN THE PATIENTS WITH ITP AND THE CONTROLS (P = 0.745 AND 0.747, RESPECTIVELY). NO SIGNIFICANT DIFFERENCE WAS OBSERVED IN GENOTYPE AND ALLELE DISTRIBUTION BETWEEN THE TWO GROUPS WHEN STRATIFIED BY THE AGE. THE SIMILAR RESULTS WERE SHOWN AMONG THE FOUR GROUPS OF PATIENTS WITH ITP: ACUTE CHILDHOOD, CHRONIC CHILDHOOD, ACUTE ADULT, AND CHRONIC ADULT. CONCLUSION: THIS POLYMORPHISM WAS DISTRIBUTED SIMILARLY BETWEEN THE PATIENTS WITH ITP AND THE CONTROLS. IT DEMONSTRATED THAT IT MAY NOT BE USED AS A STRATIFICATION MARKER TO PREDICT THE SUSCEPTIBILITY TO ITP, AT LEAST IN THE POPULATION OF NORTH CHINA. 2008 6 2205 31 EPIGENETIC MODIFICATION OF THE X CHROMOSOME INFLUENCES SUSCEPTIBILITY TO POLYCYSTIC OVARY SYNDROME. CONTEXT: THE CAUSE OF POLYCYSTIC OVARY SYNDROME (PCOS) IS UNKNOWN, ALTHOUGH GENETIC AND ENVIRONMENTAL INFLUENCES ARE CLEARLY IMPLICATED. SOME GENETIC STUDIES HAVE SUGGESTED THE INVOLVEMENT OF X-LINKED GENES IN PCOS, BUT THE INFLUENCE OF X CHROMOSOME INACTIVATION (XCI) ON MANIFESTATION OF THIS DISORDER HAS NOT PREVIOUSLY BEEN EXAMINED. OBJECTIVE: THE OBJECTIVE OF THE STUDY WAS TO TEST THE NULL HYPOTHESIS THAT XCI HAS NO INFLUENCE ON CLINICAL PRESENTATION OF PCOS. DESIGN: WE EXAMINED PATTERNS OF XCI BETWEEN SISTER PAIRS WITH THE SAME GENOTYPE AT A POLYMORPHIC LOCUS ON THE X CHROMOSOME IN FAMILIES WITH PCOS. SETTING: THE STUDY WAS CONDUCTED AT A PRIVATE PRACTICE. PARTICIPANTS: PCOS WAS DEFINED AS HYPERANDROGENEMIA WITH CHRONIC ANOVULATION. FORTY FAMILIES WERE STUDIED IN WHICH DNA WAS OBTAINED FROM AT LEAST ONE PARENT, THE PROBAND, AND ONE SISTER THAT COULD BE ACCURATELY DIAGNOSED AS BEING AFFECTED OR UNAFFECTED. MAIN OUTCOME MEASURE(S): RELATIVE EXPRESSION OF TWO X-LINKED ALLELES WAS DETERMINED, AND THE RATIO OF ONE TO THE OTHER REPRESENTED THE PATTERN OF XCI. RESULTS: THE STATISTICAL ODDS ON A DIFFERENT CLINICAL PRESENTATION BETWEEN SISTERS WAS APPROXIMATELY 29 TIMES HIGHER IN SISTER PAIRS WITH DIFFERENT PATTERNS OF XCI, COMPARED WITH SISTER PAIRS WITH THE SAME PATTERN OF XCI (ODDS RATIO 28.9; 95% CONFIDENCE INTERVAL 4.0-206; P = 0.0008). CONCLUSIONS: THIS STUDY PROVIDES EVIDENCE TO REFUTE THE NULL HYPOTHESIS AND PROPOSE A CLOSER INSPECTION OF X-LINKED GENES IN PCOS, ONE IN WHICH BOTH GENOTYPE AND EPIGENOTYPE ARE CONSIDERED. ENVIRONMENTAL DETERMINANTS OF PCOS MAY ALTER CLINICAL PRESENTATION VIA EPIGENETIC MODIFICATIONS, WHICH CURRENTLY REMAIN UNDETECTED IN TRADITIONAL GENETIC ANALYSES. 2006 7 5267 24 PROMOTER ACTIVITY-BASED CASE-CONTROL ASSOCIATION STUDY ON SLC6A4 HIGHLIGHTING HYPERMETHYLATION AND ALTERED AMYGDALA VOLUME IN MALE PATIENTS WITH SCHIZOPHRENIA. ASSOCIATIONS BETWEEN ALTERED DNA METHYLATION OF THE SEROTONIN TRANSPORTER (5-HTT)-ENCODING GENE SLC6A4 AND EARLY LIFE ADVERSITY, MOOD AND ANXIETY DISORDERS, AND AMYGDALA REACTIVITY HAVE BEEN REPORTED. HOWEVER, FEW STUDIES HAVE EXAMINED EPIGENETIC ALTERATIONS OF SLC6A4 IN SCHIZOPHRENIA (SZ). WE EXAMINED CPG SITES OF SLC6A4, WHOSE DNA METHYLATION LEVELS HAVE BEEN REPORTED TO BE ALTERED IN BIPOLAR DISORDER, USING 3 INDEPENDENT COHORTS OF PATIENTS WITH SZ AND AGE-MATCHED CONTROLS. WE FOUND SIGNIFICANT HYPERMETHYLATION OF A CPG SITE IN SLC6A4 IN MALE PATIENTS WITH SZ IN ALL 3 COHORTS. WE SHOWED THAT CHRONIC ADMINISTRATION OF RISPERIDONE DID NOT AFFECT THE DNA METHYLATION STATUS AT THIS CPG SITE USING COMMON MARMOSETS, AND THAT IN VITRO DNA METHYLATION AT THIS CPG SITE DIMINISHED THE PROMOTER ACTIVITY OF SLC6A4. WE THEN GENOTYPED THE 5-HTT-LINKED POLYMORPHIC REGION (5-HTTLPR) AND INVESTIGATED THE RELATIONSHIP AMONG 5-HTTLPR, DNA METHYLATION, AND AMYGDALA VOLUME USING BRAIN IMAGING DATA. WE FOUND THAT PATIENTS HARBORING LOW-ACTIVITY 5-HTTLPR ALLELES SHOWED HYPERMETHYLATION AND THEY SHOWED A NEGATIVE CORRELATION BETWEEN DNA METHYLATION LEVELS AND LEFT AMYGDALA VOLUMES. THESE RESULTS SUGGEST THAT HYPERMETHYLATION OF THE CPG SITE IN SLC6A4 IS INVOLVED IN THE PATHOPHYSIOLOGY OF SZ, ESPECIALLY IN MALE PATIENTS HARBORING LOW-ACTIVITY 5-HTTLPR ALLELES. 2020 8 325 28 ALLELE-SPECIFIC DNA METHYLATION LEVEL OF FKBP5 IS ASSOCIATED WITH POST-TRAUMATIC STRESS DISORDER. BACKGROUND: FK506-BINDING PROTEIN 5 (FKBP5) BINDS TO GLUCOCORTICOID RECEPTORS AND MODULATES GLUCOCORTICOID SENSITIVITY. THE FKBP5 GENE HAS BEEN IMPLICATED IN THE DYSREGULATION OF HUMAN STRESS RESPONSES, CONTRIBUTING TO THE RISK AND TREATMENT RESPONSE OF STRESS-RELATED DISORDERS. THE PRESENT STUDY EXAMINED WHETHER EPIGENETIC CHANGES IN FKBP5 ARE ASSOCIATED WITH CHRONIC POST-TRAUMATIC STRESS DISORDER (PTSD) STATUS IN THE CONTEXT OF FKBP5 GENETIC VARIATION (RS1360780 POLYMORPHISM) AMONG MALE VETERANS EXPOSED TO COMBAT TRAUMA. METHODS: KOREAN MALE VETERANS WHO SERVED ON ACTIVE DUTY DURING THE VIETNAM WAR WERE CATEGORIZED INTO 2 GROUPS: WITH PTSD (N = 123) AND WITHOUT PTSD (N = 116). THE GENOTYPE OF FKBP5 RS1360780 AND DNA METHYLATION LEVELS OF TWO CPG SITES AT THE FKBP5 INTRON 7 REGION WERE ASSESSED IN PERIPHERAL BLOOD. ANALYSIS OF COVARIANCE WAS PERFORMED TO EXAMINE MAIN AND INTERACTION EFFECTS OF PTSD STATUS AND FKBP5 GENOTYPE ON FKBP5 DNA METHYLATION LEVEL, WITH AGE, TRAUMA LEVELS, AND ALCOHOL USE AS COVARIATES. RESULTS: A SIGNIFICANT MAIN EFFECT OF FKBP5 RS1360780 AND PTSD AND AN INTERACTION EFFECT BETWEEN GENOTYPE AND PTSD STATUS WERE FOUND ON MEAN FKBP5 DNA METHYLATION LEVEL. THE T ALLELE OF RS1360780 WAS ASSOCIATED WITH LOWER FKBP5 METHYLATION LEVEL. IN ADDITION, THE PTSD GROUP SHOWED SIGNIFICANTLY HIGHER METHYLATION THAN DID THE NON-PTSD GROUP AMONG VETERANS CARRYING THE RISK T ALLELE (N = 96), WHILE NO GROUP DIFFERENCE WAS OBSERVED ON METHYLATION LEVELS AMONG VETERANS WITH THE CC GENOTYPE (N = 143). AMONG VETERANS CARRYING THE T ALLELE, FKBP5 METHYLATION LEVELS WERE POSITIVELY CORRELATED WITH THE SEVERITY OF PTSD SYMPTOMS. CONCLUSIONS: THE PRESENT STUDY DEMONSTRATED DIFFERENT FKBP5 METHYLATION LEVELS IN PTSD DEPENDING ON FKBP5 GENETIC VARIATION AMONG VETERANS EXPOSED TO COMBAT TRAUMA. THE PRESENT FINDING SUGGESTS THAT THE GENETIC AND EPIGENETIC MODULATION OF FKBP5 IS INVOLVED IN THE PATHOPHYSIOLOGY OF PTSD. FURTHER LONGITUDINAL RESEARCH INVOLVING PEOPLE EXPOSED TO TRAUMA IS REQUIRED TO UNDERSTAND CAUSAL RELATIONSHIPS OF FKBP5 IN THE DEVELOPMENT AND RECOVERY OF PTSD. 2019 9 2142 34 EPIGENETIC INVESTIGATION OF VARIABLY X CHROMOSOME INACTIVATED GENES IN MONOZYGOTIC FEMALE TWINS DISCORDANT FOR PRIMARY BILIARY CIRRHOSIS. PRIMARY BILIARY CIRRHOSIS (PBC) IS AN AUTOIMMUNE CHRONIC CHOLESTATIC LIVER DISEASE WITH A STRONG GENETIC SUSCEPTIBILITY DUE TO THE HIGH CONCORDANCE IN MONOZYGOTIC (MZ) TWINS AND A STRIKING FEMALE PREDOMINANCE. WOMEN WITH PBC MANIFEST AN ENHANCED X MONOSOMY RATE IN PERIPHERAL LYMPHOCYTES AND WE THUS HYPOTHESIZED AN X CHROMOSOME EPIGENETIC COMPONENT TO EXPLAIN PBC FEMALE PREVALENCE. WHILE MOST GENES ON THE FEMALE INACTIVE X CHROMOSOME ARE SILENCED BY PROMOTER METHYLATION FOLLOWING X CHROMOSOME INACTIVATION (XCI), APPROXIMATELY 10% OF X- LINKED GENES EXHIBIT VARIABLE ESCAPE FROM XCI IN HEALTHY FEMALES. THIS STUDY WAS DESIGNED TO TEST THE HYPOTHESIS THAT SUSCEPTIBILITY TO PBC IS MODIFIED BY ONE OR MORE X-LINKED GENE WITH VARIABLE XCI STATUS. PERIPHERAL BLOOD MRNA AND DNA SAMPLES WERE OBTAINED FROM A UNIQUE COHORT OF MZ TWIN SETS DISCORDANT AND CONCORDANT FOR PBC. TRANSCRIPT LEVELS OF THE 125 VARIABLE XCI STATUS GENES WAS DETERMINED BY QUANTITATIVE RT-PCR ANALYSIS AND TWO GENES (CLIC2 AND PIN4) WERE IDENTIFIED AS CONSISTENTLY DOWNREGULATED IN THE AFFECTED TWIN OF DISCORDANT PAIRS. BOTH CLIC2 AND PIN4 DEMONSTRATED PARTIAL AND VARIABLE METHYLATION OF CPG SITES WITHIN 300 BP OF THE TRANSCRIPTION START SITE THAT DID NOT PREDICT THE XCI STATUS. PROMOTER METHYLATION OF CLIC2 MANIFESTED NO SIGNIFICANT DIFFERENCE BETWEEN SAMPLES AND NO SIGNIFICANT CORRELATION WITH TRANSCRIPT LEVELS. PIN4 METHYLATION SHOWED A POSITIVE TREND WITH TRANSCRIPTION IN ALL SAMPLES BUT NO DIFFERENTIAL METHYLATION WAS OBSERVED BETWEEN DISCORDANT TWINS. A GENETIC POLYMORPHISM AFFECTING THE NUMBER OF CPG SITES IN THE PIN4 PROMOTER DID NOT IMPACT METHYLATION OR TRANSCRIPT LEVELS IN A HETEROZYGOUS TWIN PAIR AND SHOWED A SIMILAR FREQUENCY IN INDEPENDENT SERIES OF UNRELATED PBC CASES AND CONTROLS. OUR RESULTS SUGGEST THAT EPIGENETIC FACTORS INFLUENCING PBC ONSET ARE MORE COMPLEX THAN METHYLATION DIFFERENCES AT X-LINKED PROMOTERS AND VARIABLY 3 INACTIVATED X-LINKED GENES MAY BE CHARACTERIZED BY PARTIAL PROMOTER METHYLATION AND BIALLELIC TRANSCRIPTION. 2011 10 2766 39 EXPRESSION, POLYMORPHISM AND METHYLATION PATTERN OF INTERLEUKIN-6 IN PERIODONTAL TISSUES. PERIODONTITIS IS CONSIDERED AN INFLAMMATORY DISORDER OF BACTERIAL ETIOLOGY THAT RESULTS IN PERIODONTAL TISSUE DESTRUCTION, AS A RESULT OF COMPLEX INTERACTIONS BETWEEN PERIODONTAL PATHOGENS, HOST AND IMMUNE RESPONSE. GENETIC AND EPIGENETIC MECHANISMS MAY MODULATE THE INDIVIDUAL RESPONSE SINCE IT IS ABLE TO INFLUENCE THE GENE EXPRESSION. THE AIM OF THIS STUDY WAS TO EVALUATE THE IMPACT OF -174 G/C POLYMORPHISM AND THE METHYLATION STATUS OF THE PROMOTER REGION OF IL-6 GENE ON THE EXPRESSION OF IL-6 IN GINGIVAL SAMPLES FROM INDIVIDUALS WITH CHRONIC PERIODONTITIS. GINGIVAL BIOPSIES WERE COLLECTED FROM 21 PATIENTS WITH CHRONIC PERIODONTITIS AND 21 CONTROLS. HISTOLOGIC SECTIONS STAINED BY HEMATOXYLIN-EOSIN WERE USED FOR HISTOPATHOLOGICAL EVALUATION. THE IL-6 GENE EXPRESSION WAS ASSESSED BY QUANTITATIVE REAL-TIME PCR. THE POLYMORPHISM IL-6 -174 C/G WAS STUDIED BY POLYMERASE CHAIN REACTION (PCR) AMPLIFICATION AND RESTRICTION ENDONUCLEASE DIGESTION (HSPII). METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION WAS USED TO VERIFY THE DNA METHYLATION PATTERN. THE NUMBER OF INFLAMMATORY CELLS IN TISSUE FRAGMENTS FROM INDIVIDUALS WITH CHRONIC PERIODONTITIS WAS HIGHER THAN IN THE CONTROL GROUP AND THE INFLAMMATORY INFILTRATE WAS PREDOMINANTLY MONONUCLEAR. THE EXPRESSION OF IL-6 WAS HIGHER IN THE GROUP WITH PERIODONTITIS. IN POLYMORPHISM ASSAY, NO STATISTICAL DIFFERENCE IN THE DISTRIBUTION OF GENOTYPES AND ALLELES IN BOTH GROUPS WERE OBSERVED. THE MOST OF SAMPLES WERE PARTIALLY METHYLATED. NO DIFFERENCE WAS OBSERVED IN METHYLATION PATTERN FROM TWO DIFFERENT REGIONS OF THE IL-6 GENE AMONG GROUPS. THE HIGH EXPRESSION OF IL-6 IS AN IMPORTANT FACTOR RELATED TO CHRONIC PERIODONTITIS, BUT WAS NOT ASSOCIATED WITH METHYLATION STATUS OR THE -174 (G/C) GENETIC POLYMORPHISM, SUGGESTING THAT OTHER MECHANISMS ARE INVOLVED IN THIS GENE TRANSCRIPTION REGULATION. 2013 11 938 31 CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) RISK IS MEDIATED BY MULTIPLE ENHANCER VARIANTS WITHIN CLL RISK LOCI. CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS THE MOST COMMON ADULT LEUKEMIA IN WESTERN COUNTRIES. IT HAS A STRONG GENETIC BASIS, SHOWING A ~ 8-FOLD INCREASED RISK OF CLL IN FIRST-DEGREE RELATIVES. GENOME-WIDE ASSOCIATION STUDIES (GWAS) HAVE IDENTIFIED 41 RISK VARIANTS ACROSS 41 LOCI. HOWEVER, FOR A MAJORITY OF THE LOCI, THE FUNCTIONAL VARIANTS AND THE MECHANISMS UNDERLYING THEIR CAUSAL ROLES REMAIN UNDEFINED. HERE, WE EXAMINED THE GENETIC AND EPIGENETIC FEATURES ASSOCIATED WITH 12 INDEX VARIANTS, ALONG WITH ANY CORRELATED (R2 >/= 0.5) VARIANTS, AT THE CLL RISK LOCI LOCATED OUTSIDE OF GENE PROMOTERS. BASED ON PUBLICLY AVAILABLE CHIP-SEQ AND CHROMATIN ACCESSIBILITY DATA AS WELL AS OUR OWN CHIP-SEQ DATA FROM CLL PATIENTS, WE IDENTIFIED SIX CANDIDATE FUNCTIONAL VARIANTS AT SIX LOCI AND AT LEAST TWO CANDIDATE FUNCTIONAL VARIANTS AT EACH OF THE REMAINING SIX LOCI. THE FUNCTIONAL VARIANTS ARE PREDOMINANTLY LOCATED WITHIN ENHANCERS OR SUPER-ENHANCERS, INCLUDING BI-DIRECTIONALLY TRANSCRIBED ENHANCERS, WHICH ARE OFTEN RESTRICTED TO IMMUNE CELL TYPES. FURTHERMORE, WE FOUND THAT, AT 78% OF THE FUNCTIONAL VARIANTS, THE ALTERNATIVE ALLELES ALTERED THE TRANSCRIPTION FACTOR BINDING MOTIFS OR HISTONE MODIFICATIONS, INDICATING THE INVOLVEMENT OF THESE VARIANTS IN THE CHANGE OF LOCAL CHROMATIN STATE. FINALLY, THE ENHANCERS CARRYING FUNCTIONAL VARIANTS PHYSICALLY INTERACTED WITH GENES ENRICHED IN THE TYPE I INTERFERON SIGNALING PATHWAY, APOPTOSIS, OR TP53 NETWORK THAT ARE KNOWN TO PLAY KEY ROLES IN CLL. THESE RESULTS SUPPORT THE REGULATORY ROLES FOR INHERITED NONCODING VARIANTS IN THE PATHOGENESIS OF CLL. 2020 12 3057 34 GENOME-WIDE DNA METHYLATION ANALYSIS IN ANKYLOSING SPONDYLITIS IDENTIFIES HLA-B*27 DEPENDENT AND INDEPENDENT DNA METHYLATION CHANGES IN WHOLE BLOOD. BACKGROUND AND OBJECTIVE: ANKYLOSING SPONDYLITIS IS A CHRONIC INFLAMMATORY DISEASE CHARACTERIZED BY INFLAMMATION OF THE SACROILIAC JOINTS AND THE SPINE THAT CAN LEAD TO SIGNIFICANT PAIN, IMMOBILITY, AND DISABILITY. THE ETIOLOGY AND PATHOGENESIS OF ANKYLOSING SPONDYLITIS ARE INCOMPLETELY UNDERSTOOD, THOUGH MOST PATIENTS CARRY THE HLA-B*27 ALLELE. THE OBJECTIVE OF THIS STUDY WAS TO EVALUATE DNA METHYLATION CHANGES IN ANKYLOSING SPONDYLITIS WITH THE GOAL OF REVEALING NOVEL MECHANISTIC INSIGHTS INTO THIS DISEASE. METHODS: GENOME-WIDE DNA METHYLATION ANALYSIS WAS PERFORMED IN WHOLE BLOOD DNA SAMPLES USING THE INFINIUM METHYLATIONEPIC ARRAY IN PATIENTS WITH ANKYLOSING SPONDYLITIS COMPARED TO AGE, SEX, AND RACE MATCHED PATIENTS WITH OSTEOARTHRITIS AS A NON-INFLAMMATORY DISEASE CONTROL. WE STUDIED 24 PATIENTS WITH ANKYLOSING SPONDYLITIS, INCLUDING 12 PATIENTS WHO CARRY HLA-B*27 AND 12 PATIENTS WHO ARE HLA-B*27 NEGATIVE. DNA METHYLATION ANALYSIS WAS PERFORMED WITH ADJUSTMENT FOR BLOOD CELL COMPOSITION IN EACH SAMPLE. RESULTS: WE IDENTIFIED A TOTAL OF 67 DIFFERENTIALLY METHYLATED SITES BETWEEN ANKYLOSING SPONDYLITIS PATIENTS AND OSTEOARTHRITIS CONTROLS. HYPERMETHYLATED GENES FOUND INCLUDED GTPASE-RELATED GENES, WHILE HYPOMETHYLATED GENES INCLUDED HCP5, WHICH ENCODES A LNCRNA WITHIN THE MHC REGION, PREVIOUSLY ASSOCIATED WITH GENETIC RISK FOR PSORIASIS AND TOXIC EPIDERMAL NECROLYSIS. CARRYING HLA-B*27 WAS ASSOCIATED WITH ROBUST HYPOMETHYLATION OF HCP5, TUBULIN FOLDING COFACTOR A (TBCA) AND PHOSPHOLIPASE D FAMILY MEMBER 6 (PLD6) IN ANKYLOSING SPONDYLITIS PATIENTS. HYPOMETHYLATION WITHIN HCP5 INVOLVES A CPG SITE THAT CONTAINS A SINGLE NUCLEOTIDE POLYMORPHISM IN LINKAGE DISEQUILIBRIUM WITH HLA-B*27 AND THAT CONTROLS DNA METHYLATION AT THIS LOCUS IN AN ALLELE-SPECIFIC MANNER. CONCLUSIONS: A GENOME-WIDE DNA METHYLATION ANALYSIS IN ANKYLOSING SPONDYLITIS IDENTIFIED DNA METHYLATION PATTERNS THAT COULD PROVIDE POTENTIAL NOVEL INSIGHTS INTO THIS DISEASE. OUR FINDINGS SUGGEST THAT HLA-B*27 MIGHT PLAY A ROLE IN ANKYLOSING SPONDYLITIS IN PART THROUGH INDUCING EPIGENETIC DYSREGULATION. 2019 13 5118 26 POSSIBLE ASSOCIATION BETWEEN GERMLINE METHYLENETETRAHYDROFOLATE REDUCTASE GENE POLYMORPHISMS AND PSORIASIS RISK IN A TURKISH POPULATION. BACKGROUND: PSORIASIS IS A COMMON CHRONIC INFLAMMATORY SKIN DISEASE CAUSED BY GENETIC AND EPIGENETIC FACTORS. THERE ARE CONFLICTING RESULTS IN THE LITERATURE ABOUT THE ASSOCIATION BETWEEN PSORIASIS AND THE METHYLENETETRAHYDROFOLATE REDUCTASE GENE (MTHFR), RANGING FROM STRONG LINKAGE TO NO ASSOCIATION. AIM: TO INVESTIGATE THE ASSOCIATION BETWEEN THE GERMLINE MTHFR POLYMORPHISMS C677T AND A1298C WITH PSORIASIS RISK IN A TURKISH POPULATION. METHODS: THE STUDY ENROLLED 84 PATIENTS WITH PSORIASIS AND 212 HEALTHY CONTROLS (HCS) WITHOUT ANY HISTORY OF PSORIASIS. DNA WAS EXTRACTED FROM PERIPHERAL BLOOD SAMPLES OF PATIENTS AND HCS, AND REAL-TIME PCR WAS USED FOR GENOTYPING. RESULTS WERE COMPARED BY PEARSON CHI(2) TEST AND MULTIPLE LOGISTIC REGRESSION MODELS. RESULTS: THE FREQUENCY OF BOTH THE MTHFR 677TT AND A1298C (HOMOZYGOUS) GENOTYPES WAS STATISTICALLY SIGNIFICANTLY DIFFERENT FROM HCS. POINT MUTATIONS WERE DETECTED IN ALL PATIENTS WITH EARLY-ONSET PSORIASIS (BEFORE THE AGE OF 20 YEARS). THE T ALLELE OF MTHFR 677 AND THE C ALLELE OF MTHFR 1298 INCREASED PSORIASIS RISK BY 12.4- AND 17.0-FOLD, RESPECTIVELY, IN PATIENTS COMPARED WITH HCS. CONCLUSION: A POSSIBLE ASSOCIATION WAS DETECTED BETWEENGERMLINE MTHFR 677 C>T AND 1298 A>C GENOTYPES AND PSORIASIS RISK IN A TURKISH POPULATION. THESE RESULTS NEED TO BE CONFIRMED IN FURTHER STUDIES WITH LARGER SAMPLE SIZES. 2017 14 3056 31 GENOME-WIDE DNA METHYLATION ANALYSIS IMPLICATES ENRICHMENT OF INTERFERON PATHWAY IN AFRICAN AMERICAN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS AND EUROPEAN AMERICANS WITH LUPUS NEPHRITIS. SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) IS A CHRONIC, MULTISYSTEM, INFLAMMATORY AUTOIMMUNE DISEASE THAT DISPROPORTIONATELY AFFECTS WOMEN. TRENDS IN SLE PREVALENCE AND CLINICAL COURSE DIFFER BY ANCESTRY, WITH THOSE OF AFRICAN AMERICAN ANCESTRY PRESENTING WITH MORE ACTIVE, SEVERE AND RAPIDLY PROGRESSIVE DISEASE THAN EUROPEAN AMERICANS. PREVIOUS RESEARCH ESTABLISHED ALTERED EPIGENETIC SIGNATURES IN SLE PATIENTS COMPARED TO CONTROLS. HOWEVER, THE CONTRIBUTION OF ABERRANT DNA METHYLATION (DNAM) TO THE RISK OF SLE BY ANCESTRY AND DIFFERENCES AMONG PATIENTS WITH SLE-ASSOCIATED LUPUS NEPHRITIS (LN) HAS NOT BEEN WELL DESCRIBED. WE EVALUATED THE DNA METHYLOMES OF 87 INDIVIDUALS INCLUDING 41 SLE PATIENTS, WITH AND WITHOUT LN, AND 46 CONTROLS ENROLLED IN AN ANCESTRY DIVERSE, WELL-CHARACTERIZED COHORT STUDY OF ESTABLISHED SLE (41 SLE PATIENTS [20 SLE-LN+, 21 SLE-LN-] AND 46 SEX-, RACE- AND AGE-MATCHED CONTROLS; 55% AFRICAN AMERICAN, 45% EUROPEAN AMERICAN). PARTICIPANTS WERE GENOTYPED USING THE INFINIUM GLOBAL DIVERSITY ARRAY (GDA), AND GENETIC ANCESTRY WAS ESTIMATED USING PRINCIPAL COMPONENTS. GENOME-WIDE DNA METHYLATION WAS INITIALLY MEASURED USING THE ILLUMINA METHYLATIONEPIC 850K BEADCHIP ARRAY FOLLOWED BY METHYLATION-SPECIFIC QPCR TO VALIDATE THE METHYLATION STATUS AT PUTATIVE LOCI. DIFFERENTIALLY METHYLATED POSITIONS (DMP) WERE IDENTIFIED USING A CASE-CONTROL APPROACH ADJUSTED FOR ANCESTRY. WE IDENTIFIED A TOTAL OF 51 DMPS IN CPGS AMONG SLE PATIENTS COMPARED TO CONTROLS. GENES PROXIMAL TO THESE CPGS WERE HIGHLY ENRICHED FOR INVOLVEMENT IN TYPE I INTERFERON SIGNALING. DMPS AMONG EUROPEAN AMERICAN SLE PATIENTS WITH LN WERE SIMILAR TO AFRICAN AMERICAN SLE PATIENTS WITH AND WITHOUT LN. OUR FINDINGS WERE VALIDATED USING AN ORTHOGONAL, METHYL-SPECIFIC PCR FOR THREE SLE-ASSOCIATED DMPS NEAR OR PROXIMAL TO MX1, USP18, AND IFITM1. OUR STUDY CONFIRMS PREVIOUS REPORTS THAT DMPS IN CPGS ASSOCIATED WITH SLE ARE ENRICHED IN TYPE I INTERFERON GENES. HOWEVER, WE SHOW THAT EUROPEAN AMERICAN SLE PATIENTS WITH LN HAVE SIMILAR DNAM PATTERNS TO AFRICAN AMERICAN SLE PATIENTS IRRESPECTIVE OF LN, SUGGESTING THAT ABERRANT DNAM ALTERS ACTIVITY OF TYPE I INTERFERON PATHWAY LEADING TO MORE SEVERE DISEASE INDEPENDENT OF ANCESTRY. 2023 15 67 29 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 16 6247 32 THE METHYLATION PATTERNS OF A DISINTEGRIN AND METALLOPROTEINASE 33 GENE (ADAM33) IN ADULT ASTHMA. BACKGROUND: ASTHMA IS A COMMON CHRONIC INFLAMMATORY RESPIRATORY DISEASE. PREVIOUS STUDIES HAVE SUGGESTED THAT THE PATHOGENESIS OF ASTHMA MAY BE AFFECTED BY EPIGENETIC REGULATION. THE PURPOSE OF THIS STUDY IS TO CHARACTERIZE THE EFFECT OF THE METHYLATION OF EACH CPG SITE IN THE ADAM33 (A DISINTEGRIN AND METALLOPROTEINASE 33) GENE IN ADULT ASTHMA. METHODS: A HUMAN CPG ISLAND MICROARRAY WAS USED TO EXAMINE 4 ASTHMATIC CASES AND 4 HEALTHY CONTROLS, AND THE RESULTS SUGGESTED THAT THERE MIGHT BE DIFFERENCES IN METHYLATION WITHIN EXON 9 OF THE ADAM33 GENE. THEREFORE, WE DESIGNED A CASE-CONTROL STUDY WITH 50 ASTHMATIC PATIENTS AND 50 AGE- AND SEX-MATCHED HEALTHY CONTROLS TO EXAMINE THE RELATIONSHIP BETWEEN THE CPG METHYLATION OF THE ADAM33 GENE AND ASTHMA USING BISULFITE DEOXYRIBONUCLEIC ACID MODIFICATION AND SEQUENCING. RESULTS: BISULFITE SEQUENCING EXPERIMENTS SHOWED THAT THE 14 CPG SITES IN EXON 9 OF THE ADAM33 GENE WERE HIGHLY METHYLATED (100%) IN ALL INDIVIDUALS. THE PROPORTIONS OF METHYLATION OF THE 14 CPG SITES IN ADAM33 IN THE CASE GROUP WERE NOT DIFFERENT FROM THOSE OF THE CONTROL GROUP. THE METHYLATION OF EXON 9 OF THIS LOCUS WAS NOT ASSOCIATED WITH AGE, SEX, IGE LEVELS, OR LUNG FUNCTION. THIS STUDY FOUND NO ASSOCIATION BETWEEN THE METHYLATION OF CPG SITES IN EXON 9 OF THE ADAM33 GENE AND ADULT ASTHMA. CONCLUSIONS: THE 14 CPG SITES WERE HIGHLY METHYLATED IN THE CASE AND CONTROL GROUPS. FURTHER INVESTIGATION OF EXON 9 IN ADAM33 IN A LARGER POPULATION IS NEEDED TO EVALUATE ITS ROLE IN ASTHMA. 2013 17 3031 30 GENETICS OF RHEUMATOID ARTHRITIS. RHEUMATOID ARTHRITIS (RA) IS AN INFLAMMATORY AUTOIMMUNE DISEASE INVOLVING SYMMETRIC JOINTS AND IS GENERALLY CHARACTERIZED BY PERSISTENT PAIN, TENDERNESS, AND DESTRUCTION OF JOINTS. THE VAST MAJORITY OF RA PATIENTS PRODUCE AUTOANTIBODIES, AND IMMUNE CELL INVOLVEMENT IN DISEASE DEVELOPMENT IS WELL RECOGNIZED, AS IS THE CONTRIBUTION OF OTHER TYPES OF CELLS IN SYNOVIAL TISSUE, LIKE FIBROBLASTS. IT IS KNOWN THAT THERE ARE MAJOR GENETIC ASSOCIATIONS WITH THE HLA LOCUS, WHILE MULTIPLE NON-HLA GENETIC VARIANTS DISPLAY RELATIVELY LOW RISK OF RA. BOTH HLA AND NON-HLA ASSOCIATIONS SUGGEST THAT THE PROFILES OF GENETIC ASSOCIATIONS FOR AUTOANTIBODY-POSITIVE VS. AUTOANTIBODY-NEGATIVE RA ARE DIFFERENT. SEVERAL ALLELES OF HLA-DRB1 ARE ASSOCIATED WITH HIGH RISK FOR AUTOANTIBODY-POSITIVE RA, WITH THE STRONGEST RISK CHARACTERIZED BY VALINE AT POSITION 11 OF THE PROTEIN SEQUENCE (HLA-DRB1*04 AND *10 ALLELES). THERE IS A STRONG PROTECTIVE EFFECT FOR THE RISK OF AUTOANTIBODY-POSITIVE RA ASSOCIATED WITH HLA-DRB1*13 ALLELES. ALTHOUGH MAJOR GENETIC ASSOCIATIONS HAVE BEEN KNOWN FOR SEVERAL YEARS, UNDERSTANDING OF THE SPECIFIC MECHANISMS IN THE DEVELOPMENT OF INCREASED RISK OF RA FOR THESE VARIATIONS IS WORK IN PROGRESS. CURRENT STUDIES FOCUS ON THE BINDING OF IMMUNE RECEPTORS INVOLVED IN RECOGNITION OF PUTATIVE PEPTIDES IN ACTIVATION OF T CELLS, AS WELL AS INVESTIGATION OF CELL SIGNALING MECHANISMS. AT LEAST A PART OF RA RISK COULD BE EXPLAINED BY GENE-GENE AND GENE-ENVIRONMENT INTERACTIONS. THERE ARE CURRENTLY MORE THAN 150 CANDIDATE LOCI WITH POLYMORPHISMS THAT ASSOCIATE WITH RA, MAINLY RELATED TO SEROPOSITIVE DISEASE, AND NEW DISCOVERIES ARE ANTICIPATED IN THE FUTURE FROM INVESTIGATION OF DIVERSE HUMAN POPULATIONS. THIS NEW RESEARCH WILL HELP CREATE A STRONG FOUNDATION FOR THE CONTINUING PROCESS OF INTEGRATING GENETIC, EPIGENETIC, TRANSCRIPTOMIC, AND PROTEOMIC DATA IN STUDIES OF RA. 2022 18 4256 34 METHYLOMIC MARKERS OF PERSISTENT CHILDHOOD ASTHMA: A LONGITUDINAL STUDY OF ASTHMA-DISCORDANT MONOZYGOTIC TWINS. BACKGROUND: ASTHMA IS THE MOST COMMON CHRONIC INFLAMMATORY DISORDER IN CHILDREN. THE AETIOLOGY OF ASTHMA PATHOLOGY IS COMPLEX AND HIGHLY HETEROGENEOUS, INVOLVING THE INTERPLAY BETWEEN GENETIC AND ENVIRONMENTAL RISK FACTORS THAT IS HYPOTHESIZED TO INVOLVE EPIGENETIC PROCESSES. OUR AIM WAS TO EXPLORE WHETHER METHYLOMIC VARIATION IN EARLY CHILDHOOD IS ASSOCIATED WITH DISCORDANCE FOR ASTHMA SYMPTOMS WITHIN MONOZYGOTIC (MZ) TWIN PAIRS RECRUITED FROM THE ENVIRONMENTAL RISK (E-RISK) LONGITUDINAL TWIN STUDY. WE ALSO AIMED TO IDENTIFY DIFFERENCES IN DNA METHYLATION THAT ARE ASSOCIATED WITH ASTHMA THAT DEVELOPS IN CHILDHOOD AND PERSISTS INTO EARLY ADULTHOOD AS THESE MAY REPRESENT USEFUL PROGNOSTIC BIOMARKERS. RESULTS: WE EXAMINED GENOME-WIDE PATTERNS OF DNA METHYLATION IN BUCCAL CELL SAMPLES COLLECTED FROM 37 MZ TWIN PAIRS DISCORDANT FOR ASTHMA AT AGE 10. DNA METHYLATION AT INDIVIDUAL CPG SITES DEMONSTRATED SIGNIFICANT VARIABILITY WITHIN DISCORDANT MZ TWIN PAIRS WITH THE TOP-RANKED NOMINALLY SIGNIFICANT DIFFERENTIALLY METHYLATED POSITION (DMP) LOCATED IN THE HGSNAT GENE. WE STRATIFIED OUR ANALYSIS BY ASSESSING DNA METHYLATION DIFFERENCES IN A SUB-GROUP OF MZ TWIN PAIRS WHO REMAINED PERSISTENTLY DISCORDANT FOR ASTHMA AT AGE 18. THE TOP-RANKED NOMINALLY SIGNIFICANT DMP ASSOCIATED WITH PERSISTING ASTHMA IS LOCATED IN THE VICINITY OF THE HLX GENE, WHICH HAS BEEN PREVIOUSLY IMPLICATED IN CHILDHOOD ASTHMA. CONCLUSIONS: WE IDENTIFIED DNA METHYLATION DIFFERENCES ASSOCIATED WITH CHILDHOOD ASTHMA IN PERIPHERAL DNA SAMPLES FROM DISCORDANT MZ TWIN PAIRS. OUR DATA SUGGEST THAT DIFFERENCES IN DNA METHYLATION ASSOCIATED WITH CHILDHOOD ASTHMA WHICH PERSISTS INTO EARLY ADULTHOOD ARE DISTINCT FROM THOSE ASSOCIATED WITH ASTHMA WHICH REMITS. 2015 19 5637 29 SEROTONIN TRANSPORTER GENE POLYMORPHISMS IN SOUTHWESTERN IRANIAN PATIENTS WITH IRRITABLE BOWEL SYNDROME. BACKGROUND AND STUDY AIMS: IRRITABLE BOWEL SYNDROME IS A COMMON CHRONIC FUNCTIONAL GASTROINTESTINAL DISORDER OF UNKNOWN ETIOLOGY. SEROTONIN IS AN IMPORTANT FACTOR IN SENSORY SIGNALING IN THE BRAIN-GUT AXIS, WHICH PLAYS A KEY ROLE IN INTESTINAL MOTILITY AND SECRETION. SEROTONIN CLEARANCE IS MEDIATED BY A SPECIFIC PROTEIN CALLED THE SEROTONIN REUPTAKE TRANSPORTER. TRANSCRIPTION ACTIVITY OF THE SEROTONIN TRANSPORTER GENE IS AFFECTED BY SOME POLYMORPHISMS IN THIS GENE. THE AIM OF THIS STUDY WAS TO INVESTIGATE THE RELATIONSHIP BETWEEN SEROTONIN TRANSPORTER GENE POLYMORPHISMS AND IRRITABLE BOWEL SYNDROME. PATIENTS/MATERIAL AND METHODS: THE 5-HTTLPR, RS25531 AND STIN2VNTR POLYMORPHISMS OF THE SEROTONIN TRANSPORTER GENE WERE ANALYZED BY PCR-BASED METHODS IN 50 PATIENTS WITH IRRITABLE BOWEL SYNDROME AND 100 HEALTHY CONTROLS. RESULTS: SEROTONIN TRANSPORTER POLYMORPHISMS WERE SIMILAR IN PATIENTS AND HEALTHY CONTROLS. THERE WERE NO SIGNIFICANT DIFFERENCES IN ALLELE OR GENOTYPE FREQUENCIES BETWEEN THE TWO GROUPS. CONCLUSION: OUR FINDINGS SUGGEST THAT POLYMORPHISMS IN THE GENE ENCODING FOR THE SEROTONIN TRANSPORTER ARE NOT ASSOCIATED WITH IRRITABLE BOWEL SYNDROME. INTERACTIONS BETWEEN ENVIRONMENTAL FACTORS AND PREDISPOSING GENETIC FACTORS ARE IMPORTANT IN THE PATHOPHYSIOLOGY OF IRRITABLE BOWEL SYNDROME, AND FURTHER GENETIC AND EPIGENETIC RESEARCH MAY PROVIDE NOVEL INSIGHTS INTO THE MECHANISMS CONTRIBUTING TO THIS DISEASE. 2013 20 812 36 CHANGES IN DNA METHYLATION PROFILES OF MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME PATIENTS REFLECT SYSTEMIC DYSFUNCTIONS. BACKGROUND: MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS) IS A LIFELONG DEBILITATING DISEASE WITH A COMPLEX PATHOLOGY NOT YET CLEARLY DEFINED. SUSCEPTIBILITY TO ME/CFS INVOLVES GENETIC PREDISPOSITION AND EXPOSURE TO ENVIRONMENTAL FACTORS, SUGGESTING AN EPIGENETIC ASSOCIATION. EPIGENETIC STUDIES WITH OTHER ME/CFS COHORTS HAVE USED ARRAY-BASED TECHNOLOGY TO IDENTIFY DIFFERENTIALLY METHYLATED INDIVIDUAL SITES. CHANGES IN RNA QUANTITIES AND PROTEIN ABUNDANCE HAVE BEEN DOCUMENTED IN OUR PREVIOUS INVESTIGATIONS WITH THE SAME ME/CFS COHORT USED FOR THIS STUDY. RESULTS: DNA FROM A WELL-CHARACTERISED NEW ZEALAND COHORT OF 10 ME/CFS PATIENTS AND 10 AGE-/SEX-MATCHED HEALTHY CONTROLS WAS ISOLATED FROM PERIPHERAL BLOOD MONONUCLEAR (PBMC) CELLS, AND USED TO GENERATE REDUCED GENOME-SCALE DNA METHYLATION MAPS USING REDUCED REPRESENTATION BISULPHITE SEQUENCING (RRBS). THE SEQUENCING DATA WERE ANALYSED UTILISING THE DMAP ANALYSIS PIPELINE TO IDENTIFY DIFFERENTIALLY METHYLATED FRAGMENTS, AND THE METHYLKIT PIPELINE WAS USED TO QUANTIFY METHYLATION DIFFERENCES AT INDIVIDUAL CPG SITES. DMAP IDENTIFIED 76 DIFFERENTIALLY METHYLATED FRAGMENTS AND METHYLKIT IDENTIFIED 394 DIFFERENTIALLY METHYLATED CYTOSINES THAT INCLUDED BOTH HYPER- AND HYPO-METHYLATION. FOUR CLUSTERS WERE IDENTIFIED WHERE DIFFERENTIALLY METHYLATED DNA FRAGMENTS OVERLAPPED WITH OR WERE WITHIN CLOSE PROXIMITY TO MULTIPLE DIFFERENTIALLY METHYLATED INDIVIDUAL CYTOSINES. THESE CLUSTERS IDENTIFIED REGULATORY REGIONS FOR 17 PROTEIN ENCODING GENES RELATED TO METABOLIC AND IMMUNE ACTIVITY. ANALYSIS OF DIFFERENTIALLY METHYLATED GENE BODIES (EXONS/INTRONS) IDENTIFIED 122 UNIQUE GENES. COMPARISON WITH OTHER STUDIES ON PBMCS FROM ME/CFS PATIENTS AND CONTROLS WITH ARRAY TECHNOLOGY SHOWED 59% OF THE GENES IDENTIFIED IN THIS STUDY WERE ALSO FOUND IN ONE OR MORE OF THESE STUDIES. FUNCTIONAL PATHWAY ENRICHMENT ANALYSIS IDENTIFIED 30 ASSOCIATED PATHWAYS. THESE INCLUDED IMMUNE, METABOLIC AND NEUROLOGICAL-RELATED FUNCTIONS DIFFERENTIALLY REGULATED IN ME/CFS PATIENTS COMPARED TO THE MATCHED HEALTHY CONTROLS. CONCLUSIONS: MAJOR DIFFERENCES WERE IDENTIFIED IN THE DNA METHYLATION PATTERNS OF ME/CFS PATIENTS THAT CLEARLY DISTINGUISHED THEM FROM THE HEALTHY CONTROLS. OVER HALF FOUND IN GENE BODIES WITH RRBS IN THIS STUDY HAD BEEN IDENTIFIED IN OTHER ME/CFS STUDIES USING THE SAME CELLS BUT WITH ARRAY TECHNOLOGY. WITHIN THE ENRICHED FUNCTIONAL IMMUNE, METABOLIC AND NEUROLOGICAL PATHWAYS, A NUMBER OF ENRICHED NEUROTRANSMITTER AND NEUROPEPTIDE REACTOME PATHWAYS HIGHLIGHTED A DISTURBED NEUROLOGICAL PATHOPHYSIOLOGY WITHIN THE PATIENT GROUP. 2020