1 5260 157 PROGRESSIVE OSSEOUS HETEROPLASIA, AS AN ISOLATED ENTITY OR OVERLAPPING WITH ALBRIGHT HEREDITARY OSTEODYSTROPHY. INTRODUCTION: PROGRESSIVE OSSEOUS HETEROPLASIA (POH) IS A CONDITION OF INVASIVE HETEROTOPIC OSSIFICATION. REPORTS OF PATIENTS WITH MILD POH WITH ALBRIGHT HEREDITARY OSTEODYSTROPHY (AHO), SPECIFICALLY PSEUDOHYPOPARATHYROIDISM TYPE IA (PHP IA) WITH HORMONAL RESISTANCE, SUGGEST THE POSSIBILITY OF A COMMON MOLECULAR BASIS. GNAS HAS BEEN IMPLICATED TO ACCOUNT FOR OVERLAPPING FEATURES OF POH AND PHP IA. CASE 1: A 4-YEAR-OLD BOY WITH OBESITY, SPEECH DELAY, AND EXPANDING SUBCUTANEOUS MASSES ON BUTTOCK/FOREARM. PHYSICAL EXAM REVEALED ROUND FACIES AND BRACHYDACTYLY. BLOOD TESTS SHOWED NORMAL CA, P, MG, 25-OH VITAMIN D LEVELS BUT ELEVATED PARATHYROID HORMONE (PTH) AND THYROID-STIMULATING HORMONE (TSH). ABDOMINAL COMPUTED TOMOGRAPHY (CT) SHOWED AREAS WITH CALCIFICATIONS IN THE SUBCUTANEOUS TISSUE, FAT, AND MUSCLE. PATHOLOGY OF EXCISED TISSUE REVEALED OSSIFICATIONS. GENOMIC STUDY REVEALED NO GNAS MUTATION. HE HAD POH AND PHP IA. CASE 2: A 3-YEAR-OLD BOY WITH PAINFUL OSSIFICATIONS IN THE LEFT LOWER EXTREMITY. LAB TESTS WERE NOTABLE FOR ELEVATED PTH AND HIGH-NORMAL TSH. THE CT-SCAN SHOWED SUBCUTANEOUS/INTRAMUSCULAR CALCIFICATIONS. GENETIC TESTING SHOWED GNAS MUTATION IN EXON 12 [C.1024C>T (R342X)]. PATIENT HAD POH AND PHP IA. CASE 3: A 9-YEAR-OLD BOY WITH KNEE PAIN AND SUBCUTANEOUS OSSIFICATIONS IN BACK AND UPPER/LOWER EXTREMITY, CAUSING SIGNIFICANTLY LIMITED JOINT MOBILITY. LAB TESTS WERE NORMAL. THE CT-SCAN SHOWED AREAS CORRESPONDING TO SUBCUTANEOUS/INTRAMUSCULAR OSSIFICATIONS THROUGHOUT TORSO AND EXTREMITIES, CONSISTENT WITH POH. THERE WAS NO GNAS MUTATION. CONCLUSIONS: PATIENTS WITH HETEROTOPIC OSSIFICATIONS PRESENT WITH A WIDE SPECTRUM OF DISEASE. ALTHOUGH GNAS-BASED MUTATIONS HAVE BEEN POSTULATED TO ACCOUNT FOR OVERLAPPING FEATURES OF AHO AND POH, NORMAL DNA STUDIES IN CERTAIN PATIENTS WITH POH/AHO SUGGEST THAT THERE MAY EXIST OTHER MOLECULAR/EPIGENETIC MECHANISMS EXPLAINING THEIR OVERLAPPING FEATURES. 2015 2 3850 32 IS GENDER A FACTOR AFFECTING LONG-TERM HETEROTOPIC OSSIFICATION INCIDENCE AFTER SINGLE-LEVEL CERVICAL DISC ARTHROPLASTY? BACKGROUND: CERVICAL DISC DISEASES HAVE BEEN TREATED BY CERVICAL DISC ARTHROPLASTY (CDA). NEVERTHELESS, SOME PATIENTS WILL EXPERIENCE A MOBILITY FAILURE IN THEIR CERVICAL PROSTHESES OVER TIME BECAUSE OF HETEROTOPIC OSSIFICATION. THE AIM OF THIS STUDY WAS TO INVESTIGATE THE ROLE OF GENDER IN LONG-TERM OUTCOMES AFTER CDA. METHODS: A RETROSPECTIVE, SINGLE-CENTER STUDY OF PATIENTS WHO UNDERWENT SINGLE-LEVEL CDA WITH A BRYAN CERVICAL DISC PROSTHESIS WAS PERFORMED, INCLUDING A NARRATIVE REVIEW ABOUT GENDER DIFFERENCES IN BOTH STRUCTURAL AND BIOMECHANICAL FEATURES OF THE CERVICAL SPINE. RESULTS: STUDY PATIENTS (14 MEN, 30 WOMEN) HAD AN AVERAGE FOLLOW-UP OF 9.8 +/- 3.2 YEARS. SIGNIFICANT DIFFERENCES EMERGED BETWEEN GENDERS FOR SPECIFIC ITEMS IN NECK DISABILITY INDEX PREOPERATIVE EVALUATION, WITH WOMEN REPORTING WORSE PAIN SCORES (P = 0.05). AFTER STRATIFICATION BY AGE, WE FOUND A HIGHER PREOPERATIVE OVERALL NECK DISABILITY INDEX SCORE FOR FEMALE PATIENTS <36 YEARS OF AGE (P = 0.03). IN AN INTERGENDER, BODY MASS INDEX-SPECIFIC COMPARISON, WE ALSO FOUND A SIGNIFICANT DIFFERENCE IN NECK DISABILITY INDEX PREOPERATIVE SCORE WITH NORMAL-WEIGHT MALE PATIENTS FARING WORSE THAN OVERWEIGHT MALE PATIENTS (P = 0.05). AT A RADIOLOGICAL LEVEL, WE FOUND A TENDENCY TOWARD A HIGHER HETEROTOPIC OSSIFICATION INCIDENCE IN MALE PATIENTS (62% IN MEN, 17% IN WOMEN, P = 0.06). THE FEMALE CERVICAL SPINE HAS DISTINCTIVE FEATURES, INCLUDING BONE STRUCTURE, MUSCULAR ACTION, SOFT TISSUE RESPONSE, AND GENETIC AND EPIGENETIC RESPONSE TO OSTEOARTHRITIS. CONCLUSIONS: THE INCIDENCE OF MOBILITY FAILURE IN OUR SERIES OF SINGLE-LEVEL CDA WAS LOWER IN FEMALE PATIENTS. SEVERAL GENDER-SPECIFIC FACTORS BOTH IN STATIC AND IN DYNAMIC FEATURES MAY PLAY A SIGNIFICANT ROLE IN SPINAL PATHOLOGY AND CDA LONG-TERM RADIOLOGICAL OUTCOME. 2022 3 3488 28 IDENTIFICATION OF DNA METHYLATION ASSOCIATED ENRICHMENT PATHWAYS IN ADULTS WITH NON-SPECIFIC CHRONIC LOW BACK PAIN. CHRONIC LOW BACK PAIN (CLBP) THAT CANNOT BE ATTRIBUTABLE TO A SPECIFIC PATHOANATOMICAL CHANGE IS ASSOCIATED WITH HIGH PERSONAL AND SOCIETAL COSTS. STILL, THE UNDERLYING MECHANISM THAT CAUSES AND SUSTAINS SUCH A PHENOTYPE IS LARGELY UNKNOWN. EMERGING EVIDENCE SUGGESTS THAT EPIGENETIC CHANGES PLAY A ROLE IN CHRONIC PAIN CONDITIONS. USING REDUCED REPRESENTATION BISULFITE SEQUENCING (RRBS), WE EVALUATED DNA METHYLATION PROFILES OF ADULTS WITH NON-SPECIFIC CLBP (N = 50) AND PAIN-FREE CONTROLS (N = 48). WE IDENTIFIED 28,325 HYPERMETHYLATED AND 36,936 HYPOMETHYLATED CPG SITES (P < 0.05). AFTER CORRECTING FOR MULTIPLE TESTING, WE IDENTIFIED 159 DMRS (Q < 0.01AND METHYLATION DIFFERENCE > 10%), THE MAJORITY OF WHICH WERE LOCATED IN CPG ISLAND (50%) AND PROMOTER REGIONS (48%) ON THE ASSOCIATED GENES. THE GENES ASSOCIATED WITH THE DIFFERENTIALLY METHYLATED REGIONS WERE HIGHLY ENRICHED IN BIOLOGICAL PROCESSES THAT HAVE PREVIOUSLY BEEN IMPLICATED IN IMMUNE SIGNALING, ENDOCHONDRAL OSSIFICATION, AND G-PROTEIN COUPLED TRANSMISSIONS. OUR FINDINGS SUPPORT INFLAMMATORY ALTERATIONS AND THE ROLE OF BONE MATURATION IN CLBP. THIS STUDY SUGGESTS THAT EPIGENETIC REGULATION HAS AN IMPORTANT ROLE IN THE PATHOPHYSIOLOGY OF NON-SPECIFIC CLBP AND A BASIS FOR FUTURE STUDIES IN BIOMARKER DEVELOPMENT AND TARGETED INTERVENTIONS. 2020 4 2814 31 FIBRODYSPLASIA OSSIFICANS PROGRESSIVA: MIDDLE-AGE ONSET OF HETEROTOPIC OSSIFICATION FROM A UNIQUE MISSENSE MUTATION (C.974G>C, P.G325A) IN ACVR1. FIBRODYSPLASIA OSSIFICANS PROGRESSIVA (FOP) IS THE RARE MENDELIAN DISEASE CHARACTERIZED BY CONGENITAL MALFORMATION OF THE GREAT TOES PRECEDING HETEROTOPIC OSSIFICATION (HO) AND CAUSED BY HETEROZYGOUS ACTIVATING MUTATION OF THE ACVR1 GENE, WHICH ENCODES THE ALK2 RECEPTOR FOR BONE MORPHOGENETIC PROTEINS. EARLY ADULT LIFE IS THE LATEST REPORTED PRESENTATION FOR THE HO OF FOP. THE PATIENT OF OUR REPORT FIRST DEVELOPED HO FROM FOP AT 47 YEARS OF AGE. SHE HAD CONGENITAL HALLUX VALGUS DEFORMITY BUT DESPITE VARIOUS TRAUMAS WAS PREVIOUSLY WELL. HO BEGAN SEVERAL MONTHS AFTER A BRIEF, SEEMINGLY VIRAL, ILLNESS. SUDDEN AND PROGRESSIVE PAIN, REDNESS, WARMTH, AND SWELLING APPEARED OVER A SCAPULA. COMPUTED TOMOGRAPHY WAS REMARKABLE FOR ASYMMETRICAL THICKENING OF MUSCLES AND FASCIAL PLANES. AT FIRST, THE SIGNIFICANCE OF THE GREAT TOE ABNORMALITIES WENT UNRECOGNIZED ELSEWHERE, AND BIOPSY FOR SUSPECTED INFLAMMATORY FASCIITIS REVEALED PROLIFERATING FIBROBLASTS WITH SCATTERED INFLAMMATORY CELLS. PREDNISONE IMPROVED HER SYMPTOMS BUT, WHEN TAPERED, SWELLINGS DEVELOPED ON HER CHEST, POSTERIOR THORAX, AND FLANK, AND FOP WAS DIAGNOSED. METHYLPREDNISOLONE, METHOTREXATE, AND ALENDRONATE SEEMED TO HELP HER SYMPTOMS, BUT THE LESIONS WORSENED AND HO APPEARED AND RAPIDLY PROGRESSED. MUTATION ANALYSIS OF THE ACVR1 GENE REVEALED HETEROZYGOSITY FOR A UNIQUE MISSENSE DEFECT (C.974G>C, P.G325A) THAT PREDICTED A CONSERVATIVE (MILD) AMINO ACID CHANGE WITHIN THE KINASE DOMAIN OF ALK2. HENCE, HO IN FOP CAN BE DELAYED UNTIL MIDDLE-AGE, AND PERHAPS PROVOKED BY A VIRAL ILLNESS. NEVERTHELESS, PROGRESSION OF HO CAN THEN BE RAPID DESPITE BISPHOSPHONATE AND HIGH-DOSE IMMUNOSUPPRESSIVE THERAPY. POSSIBLY, OUR PATIENT'S LATE-ONSET HO REFLECTS HER MILD ALTERATION OF ALK2 OR SOME PROTECTIVE AND THERAPEUTICALLY USEFUL GENETIC, EPIGENETIC, OR NONGENETIC FACTOR. RECOGNITION OF PRESYMPTOMATIC INDIVIDUALS OR LATE-ONSET HO IN FOP SHOULD HAVE THESE PATIENTS AVOID TRAUMAS, TREATMENTS, AND MAYBE VIRAL ILLNESSES THAT CAN INITIATE OR EXACERBATE THE HO. IF THE DIAGNOSIS OF FOP IS UNCLEAR, ACVR1 MUTATION ANALYSIS IS AVAILABLE AT CERTIFIED LABORATORIES. 2012 5 5555 20 ROLE OF FLUORIDE INDUCED EPIGENETIC ALTERATIONS IN THE DEVELOPMENT OF SKELETAL FLUOROSIS. FLUORIDE IS AN ESSENTIAL TRACE ELEMENT REQUIRED FOR PROPER BONE AND TOOTH DEVELOPMENT. SYSTEMIC HIGH EXPOSURE TO FLUORIDE THROUGH ENVIRONMENTAL EXPOSURE (DRINKING WATER AND FOOD) MAY RESULT IN TOXICITY CAUSING A DISORDER CALLED FLUOROSIS. IN THE PRESENT STUDY, WE INVESTIGATED THE ALTERATION IN DNA METHYLATION PROFILE WITH CHRONIC EXPOSURE (30 DAYS) TO FLUORIDE (8 MG/L) AND ITS RELEVANCE IN THE DEVELOPMENT OF FLUOROSIS. WHOLE GENOME BISULFITE SEQUENCING (WGBS) WAS CARRIED OUT IN HUMAN OSTEOSARCOMA CELLS (HOS) EXPOSED TO FLUORIDE. WHOLE GENOME BISULFITE SEQUENCING (WGBS) AND FUNCTIONAL ANNOTATION OF DIFFERENTIALLY METHYLATED GENES INDICATE ALTERATIONS IN METHYLATION STATUS OF GENES INVOLVED IN BIOLOGICAL PROCESSES ASSOCIATED WITH BONE DEVELOPMENT PATHWAYS. COMBINED ANALYSIS OF PROMOTER DNA HYPER METHYLATION, STRING: FUNCTIONAL PROTEIN ASSOCIATION NETWORKS AND GENE EXPRESSION ANALYSIS REVEALED EPIGENETIC ALTERATIONS IN BMP1, METAP2, MMP11 AND BACH1 GENES, WHICH PLAYS A ROLE IN THE EXTRACELLULAR MATRIX DISASSEMBLY, COLLAGEN CATABOLIC/ORGANIZATION PROCESS, SKELETAL MORPHOGENESIS/DEVELOPMENT, OSSIFICATION AND OSTEOBLAST DEVELOPMENT. THE PRESENT STUDY SHOWS THAT FLUORIDE CAUSES PROMOTER DNA HYPERMETHYLATION IN BMP1, METAP2, MMP11 AND BACH1 GENES WITH SUBSEQUENT DOWN-REGULATION IN THEIR EXPRESSION LEVEL (RNA LEVEL). THE RESULTS IMPLIES THAT FLUORIDE INDUCED DNA HYPERMETHYLATION OF THESE GENES MAY HAMPER EXTRACELLULAR MATRIX DEPOSITION, CARTILAGE FORMATION, ANGIOGENESIS, VASCULAR SYSTEM DEVELOPMENT AND POROSITY OF BONE, THUS PROMOTE SKELETAL FLUOROSIS. 2019 6 2634 28 EPIGENOME-WIDE DNA METHYLATION PROFILING OF CONDITIONED PAIN MODULATION IN INDIVIDUALS WITH NON-SPECIFIC CHRONIC LOW BACK PAIN. BACKGROUND: THE PATHOANATOMIC CAUSE OF CHRONIC LOW BACK PAIN (CLBP) CANNOT BE IDENTIFIED FOR UP TO 90% OF INDIVIDUALS. HOWEVER, DYSFUNCTIONAL PROCESSING OF ENDOGENOUS NOCICEPTIVE INPUT, MEASURED AS CONDITIONED PAIN MODULATION (CPM), HAS BEEN ASSOCIATED WITH CLBP AND MAY INVOLVE CHANGES IN NEURONAL GENE EXPRESSION. EPIGENETIC-INDUCED CHANGES SUCH AS DNA METHYLATION (DNAM) HAVE BEEN ASSOCIATED WITH CLBP. METHODS: IN THE PRESENT STUDY, THE RELATIONSHIP BETWEEN CPM AND DNAM CHANGES IN A SAMPLE OF COMMUNITY-DWELLING ADULTS WITH NONSPECIFIC CLBP (N = 48) AND PAIN-FREE CONTROLS (PFC; N = 50) WAS EXAMINED USING REDUCED REPRESENTATION BISULFITE SEQUENCING. GENE ONTOLOGY (GO) TERM ENRICHMENT AND KYOTO ENCYCLOPEDIA OF GENES AND GENOMES (KEGG) PATHWAY ANALYSIS WERE APPLIED TO IDENTIFY KEY PATHWAYS INVOLVED IN EFFICIENT VERSUS DEFICIENT CPM. RESULTS: BASED ON CPM EFFICIENCY, WE IDENTIFIED 6006 AND 18,305 DIFFERENTIALLY METHYLATED CPG SITES (DMCS) WITH Q VALUES < 0.01 AMONG INDIVIDUALS WITH CLBP AND PFCS, RESPECTIVELY. MOST OF THE DMCS WERE HYPOMETHYLATED AND ANNOTATED TO GENES OF RELEVANCE TO PAIN, INCLUDING OPRM1, ADRB2, CACNA2D3, GNA12, LPL, NAXD, AND ASPHD1. IN BOTH CLBP AND PFC GROUPS, THE DMCS ANNOTATED GENES ENRICHED MANY GO TERMS RELEVANT TO PAIN PROCESSING, INCLUDING TRANSCRIPTION REGULATION BY RNA POLYMERASE II, NERVOUS SYSTEM DEVELOPMENT, GENERATION OF NEURONS, NEURON DIFFERENTIATION, AND NEUROGENESIS. BOTH GROUPS ALSO ENRICHED THE PATHWAYS INVOLVED IN RAP1-SIGNALING, CANCER, AND DOPAMINERGIC NEUROGENESIS. HOWEVER, MAPK-RAS SIGNALING PATHWAYS WERE ENRICHED IN THE CLBP, NOT THE PFC GROUP. CONCLUSIONS: THIS IS THE FIRST STUDY TO INVESTIGATE THE GENOME-SCALE DNA METHYLATION PROFILES OF CPM PHENOTYPE IN ADULTS WITH CLBP AND PFCS. BASED ON CPM EFFICIENCY, FEWER DMC ENRICHMENT PATHWAYS WERE UNIQUE TO THE CLBP THAN THE PFCS GROUP. OUR RESULTS SUGGEST THAT EPIGENETICALLY INDUCED MODIFICATION OF NEURONAL DEVELOPMENT/DIFFERENTIATION PATHWAYS MAY AFFECT CPM EFFICIENCY, SUGGESTING NOVEL POTENTIAL THERAPEUTIC TARGETS FOR CENTRAL SENSITIZATION. HOWEVER, CPM EFFICIENCY AND THE EXPERIENCE OF NONSPECIFIC CLBP MAY BE INDEPENDENT. FURTHER MECHANISTIC STUDIES ARE REQUIRED TO CONFIRM THE RELATIONSHIP BETWEEN CPM, CENTRAL SENSITIZATION, AND NONSPECIFIC CLBP. 2022 7 2960 21 GENETIC AND EPIGENETIC MARKERS IN THE EVALUATION OF PANCREATIC MASSES. BACKGROUND: METHYLATION MARKERS HAVE SHOWN PROMISE IN THE EARLY DIAGNOSIS OF PANCREATIC CARCINOMA. THE AIM OF THIS STUDY WAS TO ASSESS THE DIAGNOSTIC UTILITY OF HYPERMETHYLATION STATUS OF CANDIDATE GENES IN COMBINATION WITH KRAS MUTATION DETECTION IN THE EVALUATION OF PANCREATIC MASSES. EXPERIMENTAL DESIGN: SIXTY-ONE FINE NEEDLE ASPIRATES OF PANCREATIC MASSES (43 PANCREATIC ADENOCARCINOMAS AND 18 CHRONIC PANCREATITIS) WERE STUDIED. METHYLATION STATUS OF HRH2, EN1, SPARC, CDH13 AND APC WERE ANALYSED USING MELTING CURVE ANALYSIS AFTER DNA BISULFITE TREATMENT. KRAS MUTATIONS WERE ALSO ANALYSED. RESULTS: THE METHYLATION PANEL HAD A SENSITIVITY OF 73% (27 OF 37, CI 95% 56 TO 86%) AND A SPECIFICITY OF 100% WHENEVER TWO OR MORE PROMOTERS WERE FOUND HYPERMETHYLATED. KRAS MUTATIONS SHOWED A SENSITIVITY OF 77% (33 OF 43, CI 95% 62 TO 88%) AND A SPECIFICITY OF 100%. BOTH MOLECULAR ANALYSES ADDED USEFUL INFORMATION TO CYTOLOGY BY INCREASING THE NUMBER OF INFORMATIVE CASES. WHEN GENETIC AND EPIGENETIC ANALYSES WERE COMBINED SENSITIVITY WAS 84% (36 OF 43 CI 95% 69 TO 93%) MAINTAINING A 100% SPECIFICITY. CONCLUSIONS: ANALYSIS OF HYPERMETHYLATION STATUS OF A PANEL OF GENES AND KRAS MUTATION DETECTION OFFER A SIMILAR DIAGNOSTIC YIELD IN THE EVALUATION OF PANCREATIC MASSES. THE COMBINED MOLECULAR ANALYSIS INCREASES THE NUMBER OF INFORMATIVE CASES WITHOUT DIMINISHING SPECIFICITY. 2013 8 1908 25 ENRICHMENT OF GENOMIC PATHWAYS BASED ON DIFFERENTIAL DNA METHYLATION ASSOCIATED WITH CHRONIC POSTSURGICAL PAIN AND ANXIETY IN CHILDREN: A PROSPECTIVE, PILOT STUDY. WE HAVE REPORTED CHILD ANXIETY SENSITIVITY (CHILD ANXIETY SENSITIVITY INDEX [CASI]) PREDICTS CHRONIC POSTSURGICAL PAIN (CPSP). HEREIN, WE EVALUATED DNA METHYLATION PROFILES TO UNDERSTAND THE GENE-ENVIRONMENT INTERACTIONS UNDERLYING CPSP AND CASI, TO IDENTIFY SHARED, ENRICHED, GENOMIC PATHWAYS. IN 73 PROSPECTIVELY RECRUITED ADOLESCENTS UNDERGOING SPINE FUSION, PREOPERATIVE CASI AND PAIN DATA OVER 12 MONTHS AFTER SURGERY WERE COLLECTED. DNA FROM THE PERIPHERAL BLOOD OF EVALUABLE SUBJECTS WITH (N = 16) AND WITHOUT CPSP (N = 40) WERE ANALYZED USING METHYLATIONEPIC ARRAYS. WE IDENTIFIED 637 AND 2,445 DIFFERENTIALLY DNA METHYLATED POSITIONS (DMPS) ASSOCIATED WITH CPSP AND CASI, RESPECTIVELY (P 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 12 6386 29 THE ROLE OF QUANTITATIVE NPTX2 HYPERMETHYLATION AS A NOVEL SERUM DIAGNOSTIC MARKER IN PANCREATIC CANCER. OBJECTIVES: THE MAJORITY OF PANCREATIC CANCERS ARE FOUND TO BE UNRESECTABLE, AND THE ONLY CHANCE FOR CURE LIES ON EARLY DETECTION AND COMPLETE RESECTION. SEVERAL GENES HAVE BEEN DISCOVERED TO BE ABERRANTLY METHYLATED IN PRIMARY PANCREATIC CANCER TISSUE, AND THIS CANCER DNA CAN BE DETECTED IN THE PLASMA. THE AIMS OF THIS STUDY WERE TO DEVELOP A NOVEL DIAGNOSTIC MARKER BASED ON EPIGENETIC CHARACTERISTICS OF PANCREATIC CANCER. METHODS: WE ENROLLED 104 PATIENTS WITH PANCREATIC CANCER, 60 WITH CHRONIC PANCREATITIS, AND 5 WITH BENIGN BILIARY STONE DISEASES. THE BLOOD SAMPLES WERE COLLECTED BEFORE SURGERY OR ANY KINDS OF TREATMENT MODALITIES. DNA WAS EXTRACTED FROM THE PLASMA OF EACH PATIENT, AND NPTX2 (NEURONAL PENTRAXIN II) CPG ISLAND HYPERMETHYLATION WAS EXAMINED QUANTITATIVELY BY REAL-TIME POLYMERASE CHAIN REACTION. RESULTS: NPTX2 HYPERMETHYLATION LEVELS WERE SIGNIFICANTLY HIGHER COMPARED WITH CHRONIC PANCREATITIS (P = 0.016). THE SENSITIVITY AND SPECIFICITY WERE 80% AND 76%, RESPECTIVELY (CUTOFF = 0.015). NPTX2 GENE HYPERMETHYLATION LEVEL WAS SIGNIFICANTLY ELEVATED IN CORRELATION WITH HIGHER AMERICAN JOINT COMMITTEE ON CANCER STAGES. CONCLUSIONS: THE ABERRANTLY METHYLATED NPTX2 GENE MAY HELP TO DISTINGUISH BETWEEN CHRONIC PANCREATITIS AND PANCREATIC CANCER WITH CONVENTIONAL DIAGNOSTIC TOOLS AND COULD BECOME A VALUABLE DIAGNOSTIC MARKER. 2012 13 93 29 A PILOT STUDY OF PERIPHERAL BLOOD DNA METHYLATION MODELS AS PREDICTORS OF KNEE OSTEOARTHRITIS RADIOGRAPHIC PROGRESSION: DATA FROM THE OSTEOARTHRITIS INITIATIVE (OAI). KNEE OSTEOARTHRITIS (OA) IS A LEADING CAUSE OF CHRONIC DISABILITY WORLDWIDE, BUT NO DIAGNOSTIC OR PROGNOSTIC BIOMARKERS ARE AVAILABLE. INCREASING EVIDENCE SUPPORTS EPIGENETIC DYSREGULATION AS A CONTRIBUTOR TO OA PATHOGENESIS. IN THIS PILOT STUDY, WE INVESTIGATED EPIGENETIC PATTERNS IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) AS MODELS TO PREDICT FUTURE RADIOGRAPHIC PROGRESSION IN OA PATIENTS ENROLLED IN THE LONGITUDINAL OSTEOARTHRITIS INITIATIVE (OAI) STUDY. PBMC DNA WAS ANALYZED FROM BASELINE OAI VISITS IN 58 FUTURE RADIOGRAPHIC PROGRESSORS (JOINT SPACE NARROWING AT 24 MONTHS, SUSTAINED AT 48 MONTHS) COMPARED TO 58 NON-PROGRESSORS. DNA METHYLATION WAS QUANTIFIED VIA ILLUMINA MICROARRAYS AND BETA- AND M-VALUES WERE USED TO GENERATE LINEAR CLASSIFICATION MODELS. DATA WERE RANDOMLY SPLIT INTO A 60% DEVELOPMENT AND 40% VALIDATION SUBSETS, MODELS DEVELOPED AND TESTED, AND CROSS-VALIDATED IN A TOTAL OF 40 CYCLES. M-VALUE BASED MODELS OUTPERFORMED BETA-VALUE BASED MODELS (ROC-AUC 0.81 +/- 0.01 VS. 0.73 +/- 0.02, MEAN +/- SEM, COMPARISON P = 0.002), WITH A MEAN CLASSIFICATION ACCURACY OF 73 +/- 1% (MEAN +/- SEM) FOR M- AND 69 +/- 1% FOR BETA-BASED MODELS. ADJUSTING FOR COVARIATES DID NOT SIGNIFICANTLY ALTER MODEL PERFORMANCE. OUR FINDINGS SUGGEST THAT PBMC DNA METHYLATION-BASED MODELS MAY BE USEFUL AS BIOMARKERS OF OA PROGRESSION AND WARRANT ADDITIONAL EVALUATION IN LARGER PATIENT COHORTS. 2019 14 5957 24 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 15 2418 25 EPIGENETIC SIGNATURE OF CHRONIC LOW BACK PAIN IN HUMAN T CELLS. OBJECTIVE: DETERMINE IF CHRONIC LOW BACK PAIN (LBP) IS ASSOCIATED WITH DNA METHYLATION SIGNATURES IN HUMAN T CELLS THAT WILL REVEAL NOVEL MECHANISMS AND POTENTIAL THERAPEUTIC TARGETS AND EXPLORE THE FEASIBILITY OF EPIGENETIC DIAGNOSTIC MARKERS FOR PAIN-RELATED PATHOPHYSIOLOGY. METHODS: GENOME-WIDE DNA METHYLATION ANALYSIS OF 850,000 CPG SITES IN WOMEN AND MEN WITH CHRONIC LBP AND PAIN-FREE CONTROLS WAS PERFORMED. T CELLS WERE ISOLATED (DISCOVERY COHORT, N = 32) AND USED TO IDENTIFY DIFFERENTIALLY METHYLATED CPG SITES, AND GENE ONTOLOGIES AND MOLECULAR PATHWAYS WERE IDENTIFIED. A POLYGENIC DNA METHYLATION SCORE FOR LBP WAS GENERATED IN BOTH WOMEN AND MEN. VALIDATION WAS PERFORMED IN AN INDEPENDENT COHORT (VALIDATION COHORT, N = 63) OF CHRONIC LBP AND HEALTHY CONTROLS. RESULTS: ANALYSIS WITH THE DISCOVERY COHORT REVEALED A TOTAL OF 2,496 AND 419 DIFFERENTIALLY METHYLATED CPGS IN WOMEN AND MEN, RESPECTIVELY. IN WOMEN, MOST OF THESE SITES WERE HYPOMETHYLATED AND ENRICHED IN GENES WITH FUNCTIONS IN THE EXTRACELLULAR MATRIX, IN THE IMMUNE SYSTEM (IE, CYTOKINES), OR IN EPIGENETIC PROCESSES. IN MEN, A UNIQUE CHRONIC LBP DNA METHYLATION SIGNATURE WAS IDENTIFIED CHARACTERIZED BY SIGNIFICANT ENRICHMENT FOR GENES FROM THE MAJOR HISTOCOMPATIBILITY COMPLEX. SEX-SPECIFIC POLYGENIC DNA METHYLATION SCORES WERE GENERATED TO ESTIMATE THE PAIN STATUS OF EACH INDIVIDUAL AND CONFIRMED IN THE VALIDATION COHORT USING PYROSEQUENCING. CONCLUSION: THIS STUDY REVEALS SEX-SPECIFIC DNA METHYLATION SIGNATURES IN HUMAN T CELLS THAT DISCRIMINATES CHRONIC LBP PARTICIPANTS FROM HEALTHY CONTROLS. 2021 16 404 33 ANALYSIS OF EPIGENETIC AGE PREDICTORS IN PAIN-RELATED CONDITIONS. CHRONIC PAIN PREVALENCE IS HIGH WORLDWIDE AND INCREASES AT OLDER AGES. SIGNS OF PREMATURE AGING HAVE BEEN ASSOCIATED WITH CHRONIC PAIN, BUT FEW STUDIES HAVE INVESTIGATED AGING BIOMARKERS IN PAIN-RELATED CONDITIONS. A SET OF DNA METHYLATION (DNAM)-BASED ESTIMATES OF AGE, CALLED "EPIGENETIC CLOCKS," HAS BEEN PROPOSED AS BIOLOGICAL MEASURES OF AGE-RELATED ADVERSE PROCESSES, MORBIDITY, AND MORTALITY. THE AIM OF THIS STUDY IS TO ASSESS IF DIFFERENT PAIN-RELATED PHENOTYPES SHOW ALTERATIONS IN DNAM AGE. IN OUR ANALYSIS, WE CONSIDERED THREE COHORTS FOR WHICH WHOLE-BLOOD DNAM DATA WERE AVAILABLE: HEAT PAIN SENSITIVITY (HPS), INCLUDING 20 MONOZYGOTIC TWIN PAIRS DISCORDANT FOR HEAT PAIN TEMPERATURE THRESHOLD; FIBROMYALGIA (FM), INCLUDING 24 CASES AND 20 CONTROLS; AND HEADACHE, INCLUDING 22 CHRONIC MIGRAINE AND MEDICATION OVERUSE HEADACHE PATIENTS (MOH), 18 EPISODIC MIGRAINEURS (EM), AND 13 HEALTHY SUBJECTS. WE USED THE HORVATH'S EPIGENETIC AGE CALCULATOR TO OBTAIN DNAM-BASED ESTIMATES OF EPIGENETIC AGE, TELOMERE LENGTH, LEVELS OF 7 PROTEINS IN PLASMA, NUMBER OF SMOKED PACKS OF CIGARETTES PER YEAR, AND BLOOD CELL COUNTS. WE DID NOT FIND DIFFERENCES IN EPIGENETIC AGE ACCELERATION, CALCULATED USING FIVE DIFFERENT EPIGENETIC CLOCKS, BETWEEN SUBJECTS DISCORDANT FOR PAIN-RELATED PHENOTYPES. TWINS WITH HIGH HPS HAD INCREASED CD8+ T CELL COUNTS (NOMINAL P = 0.028). HPS THRESHOLDS WERE NEGATIVELY ASSOCIATED WITH ESTIMATED LEVELS OF GDF15 (NOMINAL P = 0.008). FM PATIENTS SHOWED DECREASED NAIVE CD4+ T CELL COUNTS COMPARED WITH CONTROLS (NOMINAL P = 0.015). THE SEVERITY OF FM MANIFESTATIONS EXPRESSED THROUGH VARIOUS EVALUATION TESTS WAS ASSOCIATED WITH DECREASED LEVELS OF LEPTIN, SHORTER LENGTH OF TELOMERES, AND REDUCED CD8+ T AND NATURAL KILLER CELL COUNTS (NOMINAL P < 0.05), WHILE THE DURATION OF PAINFUL SYMPTOMS WAS POSITIVELY ASSOCIATED WITH TELOMERE LENGTH (NOMINAL P = 0.034). NO DIFFERENCES IN DNAM-BASED ESTIMATES WERE DETECTED FOR MOH OR EM COMPARED WITH CONTROLS. IN SUMMARY, OUR STUDY SUGGESTS THAT HPS, FM, AND MOH/EM DO NOT SHOW SIGNS OF EPIGENETIC AGE ACCELERATION IN WHOLE BLOOD, WHILE HPS AND FM ARE ASSOCIATED WITH DNAM-BASED ESTIMATES OF IMMUNOLOGICAL PARAMETERS, PLASMA PROTEINS, AND TELOMERE LENGTH. FUTURE STUDIES SHOULD EXTEND THESE OBSERVATIONS IN LARGER COHORTS. 2020 17 353 29 ALTERED LEVELS OF IMMUNE-REGULATORY MICRORNAS IN PLASMA SAMPLES OF PATIENTS WITH LUPUS NEPHRITIS. INTRODUCTION: LUPUS NEPHRITIS (LN) IS A MAJOR CAUSE OF MORTALITY AND MORBIDITY IN THE PATIENTS WITH LUPUS, A CHRONIC AUTOIMMUNE DISEASE. THE ROLE OF GENETIC AND EPIGENETIC FACTORS IS EMPHASIZED IN THE PATHOGENESIS OF LN. THE AIM OF THE PRESENT STUDY WAS TO EVALUATE THE LEVELS OF IMMUNE-REGULATORY MICRORNAS (E.G., MIR-31, MIR-125A, MIR-142-3P, MIR-146A, AND MIR-155) IN PLASMA SAMPLES OF PATIENTS WITH LN. METHODS: IN THIS STUDY, 26 PATIENTS WITH LN AND 26 HEALTHY INDIVIDUALS WERE INCLUDED. THE PLASMA LEVELS OF THE MICRORNAS WERE EVALUATED BY A QUANTITATIVE REAL-TIME PCR. MOREOVER, THE CORRELATION OF CIRCULATING PLASMA MICRORNAS WITH DISEASE ACTIVITY AND PATHOLOGICAL FINDINGS ALONG WITH THEIR ABILITY TO DISTINGUISH PATIENTS WITH LN WERE ASSESSED. RESULTS: PLASMA LEVELS OF MIR-125A (P = 0.048), MIR-146A (P = 0.005), AND MIR-155 (P< 0.001) WERE SIGNIFICANTLY HIGHER IN COMPARISON BETWEEN THE CASES AND CONTROLS. THE PLASMA LEVEL OF MIR-146A SIGNIFICANTLY CORRELATED WITH THE LEVEL OF ANTI-DOUBLE STRAND-DNA ANTIBODY AND PROTEINURIA. MOREOVER, THERE WAS A SIGNIFICANT CORRELATION BETWEEN MIR-142-3P LEVELS AND DISEASE CHRONICITY AND ACTIVITY INDEX (P <0.05). THE MULTIVARIATE ROC CURVE ANALYSIS INDICATED THE PLASMA CIRCULATING MIR-125A, MIR-142-3P, MIR-146, AND MIR-155 TOGETHER COULD DISCRIMINATE MOST OF THE PATIENTS WITH LN FROM CONTROLS WITH AREA AN UNDER CURVE (AUC) OF 0.89 [95% CI, 0.80-0.98, P<0.001], 88% SENSITIVITY, AND 78% SPECIFICITY. CONCLUSION: BASED ON THE FINDINGS OF THE PRESENT STUDY, THE STUDIED MICRORNAS MAY BE INVOLVED IN THE PATHOGENESIS AND DEVELOPMENT OF LN AND HAVE THE POTENTIAL TO BE USED AS DIAGNOSTIC AND THERAPEUTIC MARKERS IN LN. 2018 18 2031 19 EPIGENETIC CHANGES IN LYMPHOCYTES OF SOLVENT-EXPOSED INDIVIDUALS. AIM: WE INVESTIGATED GLOBAL DNA METHYLATION ALTERATIONS IN LYMPHOCYTES OF SOLVENT WORKERS AND CHRONIC TOXIC ENCEPHALOPATHY (CTE) PATIENTS AND EXPLORED POTENTIAL GENE-ENVIRONMENT INTERACTIONS FOR GST. POPULATION & METHODS: A CROSS-SECTIONAL STUDY WAS SET UP IN 41 REFERENTS, 128 SOLVENT WORKERS AND 23 CTE PATIENTS. RESULTS: WE FOUND A GLOBAL DNA HYPERMETHYLATION IN THE SOLVENT-EXPOSED POPULATION COMPARED WITH THE REFERENTS (P = 0.001, R = -0.544). GLOBAL DNA METHYLATION WAS NEGATIVELY ASSOCIATED WITH EXPOSURE. FURTHERMORE, GSTP1 GENOTYPIC POLYMORPHISM WAS FOUND TO BE SIGNIFICANTLY ASSOCIATED (P = 0.033) WITH GLOBAL DNA HYPOMETHYLATION, WHICH INDICATES A POTENTIAL ROLE FOR GENE-ENVIRONMENT INTERACTION IN THE ETIOLOGY OF SOLVENT-INDUCED NEUROBEHAVIORAL DISORDERS. CONCLUSION: THIS STUDY INDICATES THAT SOLVENT-INDUCED DNA METHYLATION ALTERATIONS HAVE AN IMPACT ON NEUROTOXICITY AND DEVELOPMENT OF CTE. 2012 19 2633 28 EPIGENOME-WIDE DNA METHYLATION PATTERNS ASSOCIATED WITH FATIGUE IN PRIMARY SJOGREN'S SYNDROME. OBJECTIVE: CHRONIC FATIGUE IS A COMMON, DISABLING AND POORLY UNDERSTOOD PHENOMENON. RECENT STUDIES INDICATE THAT EPIGENETIC MECHANISMS MAY BE INVOLVED IN THE EXPRESSION OF FATIGUE, A PROMINENT FEATURE OF PRIMARY SS (PSS). THE AIM OF THIS STUDY WAS TO INVESTIGATE WHETHER DNA METHYLATION PROFILES OF WHOLE BLOOD ARE ASSOCIATED WITH FATIGUE IN PATIENTS WITH PSS. METHODS: FORTY-EIGHT PSS PATIENTS WITH HIGH (N = 24) OR LOW (N = 24) FATIGUE AS MEASURED BY A VISUAL ANALOGUE SCALE WERE INCLUDED. GENOME-WIDE DNA METHYLATION WAS INVESTIGATED USING THE ILLUMINA HUMANMETHYLATION450 BEADCHIP ARRAY. AFTER QUALITY CONTROL, A TOTAL OF 383 358 CYTOSINE-PHOSPHATE-GUANINE (CPG) SITES REMAINED FOR FURTHER ANALYSIS. AGE, SEX AND DIFFERENTIAL CELL COUNT ESTIMATES WERE INCLUDED AS COVARIATES IN THE ASSOCIATION MODEL. A FALSE DISCOVERY RATE-CORRECTED P < 0.05 WAS CONSIDERED SIGNIFICANT, AND A CUT-OFF OF 3% AVERAGE DIFFERENCE IN METHYLATION LEVELS BETWEEN HIGH- AND LOW-FATIGUE PATIENTS WAS APPLIED. RESULTS: A TOTAL OF 251 DIFFERENTIALLY METHYLATED CPG SITES WERE ASSOCIATED WITH FATIGUE. THE CPG SITE WITH THE MOST PRONOUNCED HYPOMETHYLATION IN PSS HIGH FATIGUE ANNOTATED TO THE SBF2-ANTISENSE RNA1 GENE. THE MOST DISTINCT HYPERMETHYLATION WAS OBSERVED AT A CPG SITE ANNOTATED TO THE LYMPHOTOXIN ALPHA GENE. FUNCTIONAL PATHWAY ANALYSIS OF GENES WITH DIFFERENTLY METHYLATED CPG SITES IN SUBJECTS WITH HIGH VS LOW FATIGUE REVEALED ENRICHMENT IN SEVERAL PATHWAYS ASSOCIATED WITH INNATE AND ADAPTIVE IMMUNITY. CONCLUSION: SOME GENES INVOLVED IN REGULATION OF THE IMMUNE SYSTEM AND IN INFLAMMATION ARE DIFFERENTLY METHYLATED IN PSS PATIENTS WITH HIGH VS LOW FATIGUE. THESE FINDINGS POINT TO FUNCTIONAL NETWORKS THAT MAY UNDERLIE FATIGUE. EPIGENETIC CHANGES COULD CONSTITUTE A FATIGUE-REGULATING MECHANISM IN PSS. 2016 20 812 33 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