1 2351 144 EPIGENETIC REGULATION OF NEWBORNS' IMPRINTED GENES RELATED TO GESTATIONAL GROWTH: PATTERNING BY PARENTAL RACE/ETHNICITY AND MATERNAL SOCIOECONOMIC STATUS. BACKGROUND: CHILDREN BORN TO PARENTS WITH LOWER INCOME AND EDUCATION ARE AT RISK FOR OBESITY AND LATER-LIFE RISK OF COMMON CHRONIC DISEASES, AND EPIGENETICS HAS BEEN HYPOTHESISED TO LINK THESE ASSOCIATIONS. HOWEVER, EPIGENETIC TARGETS ARE UNKNOWN. WE FOCUS ON A CLUSTER OF WELL-CHARACTERISED GENOMICALLY IMPRINTED GENES BECAUSE THEIR MONOALLELIC EXPRESSION IS REGULATED BY DNA METHYLATION AT DIFFERENTIALLY METHYLATED REGIONS (DMRS), ARE CRITICAL IN FETAL GROWTH, AND DNA METHYLATION PATTERNS AT BIRTH HAVE BEEN ASSOCIATED WITH INCREASED RISK OF BIRTH WEIGHT EXTREMES AND OVERWEIGHT STATUS OR OBESITY IN EARLY CHILDHOOD. METHODS: WE MEASURED DNA METHYLATION AT DMRS REGULATING GENOMICALLY IMPRINTED DOMAINS (IGF2/H19, DLK1/MEG3, NNAT AND PLAGL1) USING UMBILICAL CORD BLOOD LEUCOCYTES FROM 619 INFANTS RECRUITED IN DURHAM, NORTH CAROLINA IN 2010-2011. WE EXAMINED DIFFERENCES IN DNA METHYLATION LEVELS BY RACE/ETHNICITY OF BOTH PARENTS, AND THE ROLE THAT MATERNAL SOCIOECONOMIC STATUS (SES) MAY PLAY IN THE ASSOCIATION BETWEEN RACE/ETHNIC EPIGENETIC DIFFERENCES. RESULTS: UNADJUSTED RACE/ETHNIC DIFFERENCES ONLY WERE EVIDENT FOR DMRS REGULATING MEG3 AND IGF2; RACE/ETHNIC DIFFERENCES PERSISTED IN IGF2/H19 AND NNAT AFTER ACCOUNTING FOR INCOME AND EDUCATION. CONCLUSIONS: RESULTS SUGGEST THAT PARENTAL FACTORS MAY NOT ONLY INFLUENCE DNA METHYLATION, BUT ALSO DO SO IN WAYS THAT VARY BY DMR. FINDINGS SUPPORT THE HYPOTHESIS THAT EPIGENETICS MAY LINK THE OBSERVED LOWER SES DURING THE PRENATAL PERIOD AND POOR OUTCOMES SUCH AS LOW BIRTH WEIGHT; LOWER BIRTH WEIGHT HAS PREVIOUSLY BEEN ASSOCIATED WITH ADULT-ONSET CHRONIC DISEASES AND CONDITIONS THAT INCLUDE CARDIOVASCULAR DISEASES, DIABETES, OBESITY AND SOME CANCERS.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
2 2903  54 GENDER-SPECIFIC METHYLATION DIFFERENCES IN RELATION TO PRENATAL EXPOSURE TO CIGARETTE SMOKE. EPIGENETIC ALTERATIONS MAY MECHANISTICALLY EXPLAIN THE DEVELOPMENTAL ORIGINS OF ADULT DISEASE, NAMELY THE HYPOTHESIS THAT MANY COMPLEX ADULT CHRONIC DISEASES ORIGINATE AS A RESULT OF CONDITIONS ENCOUNTERED IN UTERO. IF TRUE, EPIGENETICALLY REGULATED IMPRINTED GENES, CRITICAL TO NORMAL GROWTH AND DEVELOPMENT, MAY PARTIALLY MEDIATE THESE OUTCOMES. WE DETERMINED THE INFLUENCE OF IN UTERO EXPOSURE TO CIGARETTE SMOKING ON METHYLATION AT TWO DIFFERENTIALLY METHYLATED REGIONS (DMRS) REGULATING INSULIN-LIKE GROWTH FACTOR 2 (IGF2) AND H19, AND HOW THIS MIGHT RELATE TO BIRTH WEIGHT OF INFANTS BORN TO 418 PREGNANT WOMEN. SMOKING STATUS WAS ASCERTAINED THROUGH SELF-REPORT AND MEDICAL RECORDS. BISULFITE PYROSEQUENCING WAS USED TO MEASURE METHYLATION IN UMBILICAL CORD BLOOD DNAS. LEAST SQUARES DNA METHYLATION MEANS AT EACH DMR AND BIRTH WEIGHT WERE COMPARED BETWEEN INFANTS OF SMOKERS AND NON-SMOKERS, USING GENERALIZED LINEAR MODELS. WHILE THERE WERE NO SIGNIFICANT DIFFERENCES AT THE H19 DMR, INFANTS BORN TO SMOKERS HAD HIGHER METHYLATION AT THE IGF2 DMR THAN THOSE BORN TO NEVER SMOKERS OR THOSE WHO QUIT DURING PREGNANCY (49.5%, SD=8.0 VERSUS 46.6%, SD=5.6 AND 45.8%, SD=6.3, RESPECTIVELY; P=0.0002). THE SMOKING-RELATED INCREASE IN METHYLATION WAS MOST PRONOUNCED IN MALE OFFSPRING (P FOR SEX INTERACTION=0.03), FOR WHOM APPROXIMATELY 20% OF SMOKING-RELATED LOW BIRTH WEIGHT WAS MEDIATED BY DNA METHYLATION AT THE IGF2 DMR. OUR FINDINGS SUGGEST THAT IGF2 DMR PLASTICITY IS AN IMPORTANT MECHANISM BY WHICH IN UTERO ADJUSTMENTS TO ENVIRONMENTAL TOXICANTS ARE CONFERRED. LARGER STUDIES TO REPLICATE THESE FINDINGS ARE REQUIRED.	2012	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
3  649  54 BIRTHWEIGHT, MATERNAL WEIGHT TRAJECTORIES AND GLOBAL DNA METHYLATION OF LINE-1 REPETITIVE ELEMENTS. LOW BIRTHWEIGHT, PREMATURE BIRTH, INTRAUTERINE GROWTH RETARDATION, AND MATERNAL MALNUTRITION HAVE BEEN RELATED TO AN INCREASED RISK OF CARDIOVASCULAR DISEASE, TYPE 2 DIABETES MELLITUS, OBESITY, AND NEUROPSYCHIATRIC DISORDERS LATER IN LIFE. CONVERSELY, HIGH BIRTHWEIGHT HAS BEEN LINKED TO FUTURE RISK OF CANCER. GLOBAL DNA METHYLATION ESTIMATED BY THE METHYLATION OF REPETITIVE SEQUENCES IN THE GENOME IS AN INDICATOR OF SUSCEPTIBILITY TO CHRONIC DISEASES. WE USED DATA AND BIOSPECIMENS FROM AN EPIGENETIC BIRTH COHORT TO EXPLORE THE ASSOCIATION BETWEEN TRAJECTORIES OF FETAL AND MATERNAL WEIGHT AND LINE-1 METHYLATION IN 319 MOTHER-CHILD DYADS. NEWBORNS WITH LOW OR HIGH BIRTHWEIGHT HAD SIGNIFICANTLY LOWER LINE-1 METHYLATION LEVELS IN THEIR CORD BLOOD COMPARED TO NORMAL WEIGHT INFANTS AFTER ADJUSTING FOR GESTATIONAL AGE, SEX OF THE CHILD, MATERNAL AGE AT DELIVERY, AND MATERNAL SMOKING DURING PREGNANCY (P = 0.007 AND P = 0.036, RESPECTIVELY), BUT THE MAGNITUDE OF THE DIFFERENCE WAS SMALL. INFANTS BORN PREMATURELY ALSO HAD LOWER LINE-1 METHYLATION LEVELS IN CORD BLOOD COMPARED TO TERM INFANTS, AND THIS DIFFERENCE, THOUGH SMALL, WAS STATISTICALLY SIGNIFICANT (P = 0.004). WE DID NOT FIND IMPORTANT ASSOCIATIONS BETWEEN MATERNAL PREPREGNANCY BMI OR GESTATIONAL WEIGHT GAIN AND GLOBAL METHYLATION OF THE CORD BLOOD OR FETAL PLACENTAL TISSUE. IN CONCLUSION, WE FOUND SIGNIFICANT DIFFERENCES IN CORD BLOOD LINE-1 METHYLATION AMONG NEWBORNS WITH LOW AND HIGH BIRTHWEIGHT AS WELL AS AMONG PREMATURELY BORN INFANTS. FUTURE STUDIES MAY ELUCIDATE WHETHER CHROMOSOMAL INSTABILITIES OR OTHER FUNCTIONAL CONSEQUENCES OF THESE CHANGES CONTRIBUTE TO THE INCREASED RISK OF CHRONIC DISEASES AMONG INDIVIDUALS WITH THESE CHARACTERISTICS.	2011	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
4  518  67 ASSOCIATIONS BETWEEN ANTIBIOTIC EXPOSURE DURING PREGNANCY, BIRTH WEIGHT AND ABERRANT METHYLATION AT IMPRINTED GENES AMONG OFFSPRING. OBJECTIVES: LOW BIRTH WEIGHT (LBW) HAS BEEN ASSOCIATED WITH COMMON ADULT-ONSET CHRONIC DISEASES, INCLUDING OBESITY, CARDIOVASCULAR DISEASE, TYPE II DIABETES AND SOME CANCERS. THE ETIOLOGY OF LBW IS MULTI-FACTORIAL. HOWEVER, RECENT EVIDENCE SUGGESTS EXPOSURE TO ANTIBIOTICS MAY ALSO INCREASE THE RISK OF LBW. THE MECHANISMS UNDERLYING THIS ASSOCIATION ARE UNKNOWN, ALTHOUGH EPIGENETIC MECHANISMS ARE HYPOTHESIZED. IN THIS STUDY, WE EVALUATED THE ASSOCIATION BETWEEN MATERNAL ANTIBIOTIC USE AND LBW AND EXAMINED THE POTENTIAL ROLE OF ALTERED DNA METHYLATION THAT CONTROLS GROWTH REGULATORY IMPRINTED GENES IN THESE ASSOCIATIONS. METHODS: BETWEEN 2009-2011, 397 PREGNANT WOMEN WERE ENROLLED AND FOLLOWED UNTIL DELIVERY. PRENATAL ANTIBIOTIC USE WAS ASCERTAINED THROUGH MATERNAL SELF-REPORT. IMPRINTED GENES METHYLATION LEVELS WERE MEASURED AT DIFFERENTIALLY METHYLATED REGIONS (DMRS) USING BISULFITE PYROSEQUENCING. GENERALIZED LINEAR MODELS WERE USED TO EXAMINE ASSOCIATIONS AMONG ANTIBIOTIC USE, BIRTH WEIGHT AND DMR METHYLATION FRACTIONS. RESULTS: AFTER ADJUSTING FOR INFANT GENDER, RACE/ETHNICITY, MATERNAL BODY MASS INDEX, DELIVERY ROUTE, GESTATIONAL WEIGHT GAIN, GESTATIONAL AGE AT DELIVERY, FOLIC ACID INTAKE, PHYSICAL ACTIVITY, MATERNAL SMOKING AND PARITY, ANTIBIOTIC USE DURING PREGNANCY WAS ASSOCIATED WITH 138 G LOWER BIRTH WEIGHT COMPARED WITH NON-ANTIBIOTIC USE (BETA-COEFFICIENT=-132.99, S.E.=50.70, P=0.008). THESE ASSOCIATIONS WERE STRONGEST IN NEWBORNS OF WOMEN WHO REPORTED ANTIBIOTIC USE OTHER THAN PENICILLINS (BETA-COEFFICIENT=-135.57, S.E.=57.38, P=0.02). METHYLATION AT FIVE DMRS, IGF2 (P=0.05), H19 (P=0.15), PLAGL1 (P=0.01), MEG3 (P=0.006) AND PEG3 (P=0.08), WAS ASSOCIATED WITH MATERNAL ANTIBIOTIC USE; AMONG THESE, ONLY METHYLATION AT THE PLAGL1 DMR WAS ALSO ASSOCIATED WITH BIRTH WEIGHT. CONCLUSION: WE REPORT AN INVERSE ASSOCIATION BETWEEN IN UTERO EXPOSURE TO ANTIBIOTICS AND LOWER INFANT BIRTH WEIGHT AND PROVIDE THE FIRST EMPIRICAL EVIDENCE SUPPORTING IMPRINTED GENE PLASTICITY IN THESE ASSOCIATIONS.	2013	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
5  520  46 ASSOCIATIONS BETWEEN MATERNAL PRENATAL STRESS, METHYLATION CHANGES IN IGF1 AND IGF2, AND BIRTH WEIGHT. MATERNAL STRESS HAS BEEN LINKED TO LOW BIRTH WEIGHT IN NEWBORNS. ONE POTENTIAL PATHWAY INVOLVES EPIGENETIC CHANGES AT CANDIDATE GENES THAT MAY MEDIATE THE EFFECTS OF PRENATAL MATERNAL STRESS ON BIRTH WEIGHT. THIS RELATIONSHIP HAS BEEN DOCUMENTED IN STRESS-RELATED GENES, SUCH AS NR3C1. THERE IS LESS LITERATURE EXPLORING THE EFFECT OF STRESS ON GROWTH-RELATED GENES. IGF1 AND IGF2 HAVE BEEN IMPLICATED IN FETAL GROWTH AND DEVELOPMENT, THOUGH VIA DIFFERENT MECHANISMS AS IGF2 IS UNDER IMPRINTING CONTROL. IN THIS STUDY, WE TESTED FOR ASSOCIATIONS BETWEEN PRENATAL STRESS, METHYLATION OF IGF1 AND IGF2, AND BIRTH WEIGHT. A TOTAL OF 24 MOTHER-NEWBORN DYADS IN THE DEMOCRATIC REPUBLIC OF CONGO WERE ENROLLED. ETHNOGRAPHIC INTERVIEWS WERE CONDUCTED WITH MOTHERS AT DELIVERY TO GATHER CULTURALLY RELEVANT WAR-RELATED AND CHRONIC STRESSORS. DNA METHYLATION DATA WERE GENERATED FROM MATERNAL VENOUS, CORD BLOOD AND PLACENTAL TISSUE SAMPLES. MULTIVARIATE REGRESSIONS WERE USED TO TEST FOR ASSOCIATIONS BETWEEN STRESS MEASURES, DNA METHYLATION AND BIRTH WEIGHT IN EACH OF THE THREE TISSUE TYPES. WE FOUND AN ASSOCIATION BETWEEN IGF2 METHYLATION IN MATERNAL BLOOD AND BIRTH WEIGHT. PREVIOUS LITERATURE ON THE RELATIONSHIP BETWEEN IGF2 METHYLATION AND BIRTH WEIGHT HAS FOCUSED ON METHYLATION AT KNOWN DIFFERENTIALLY METHYLATED REGIONS IN CORD BLOOD OR PLACENTAL SAMPLES. OUR FINDINGS INDICATE THERE MAY BE LINKS BETWEEN THE MATERNAL EPIGENOME AND LOW BIRTH WEIGHT THAT RELY ON MECHANISMS OUTSIDE KNOWN IMPRINTING PATHWAYS. IT THUS MAY BE IMPORTANT TO CONSIDER THE EFFECT OF MATERNAL EXPOSURES AND EPIGENETIC PROFILES ON BIRTH WEIGHT EVEN IN THE SETTING OF MATERNALLY IMPRINTED GENES SUCH AS IGF2.	2018	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
6 6089  56 THE EFFECTS OF DEPRESSION AND USE OF ANTIDEPRESSIVE MEDICINES DURING PREGNANCY ON THE METHYLATION STATUS OF THE IGF2 IMPRINTED CONTROL REGIONS IN THE OFFSPRING. IN UTERO EXPOSURES TO ENVIRONMENTAL FACTORS MAY RESULT IN PERSISTENT EPIGENETIC MODIFICATIONS AFFECTING NORMAL DEVELOPMENT AND SUSCEPTIBILITY TO CHRONIC DISEASES IN LATER LIFE. WE EXPLORED THE RELATIONSHIP BETWEEN EXPOSURE OF THE GROWING FETUS TO MATERNAL DEPRESSION OR ANTIDEPRESSANTS AND DNA METHYLATION AT TWO DIFFERENTIALLY METHYLATED REGIONS (DMRS) OF THE IMPRINTED INSULIN-LIKE GROWTH FACTOR 2 (IGF2) GENE. ABERRANT DNA METHYLATION AT THE IGF2 AND NEIGHBORING H19 DMRS HAS BEEN ASSOCIATED WITH DEREGULATED IGF2 EXPRESSION, CHILDHOOD CANCERS AND SEVERAL CHRONIC DISEASES DURING ADULTHOOD. OUR STUDY POPULATION IS COMPRISED OF PREGNANT MOTHERS AND THEIR NEWBORNS (N = 436), AS PART OF THE NEWBORN EPIGENETICS STUDY (NEST). A STANDARDIZED QUESTIONNAIRE WAS COMPLETED AND MEDICAL RECORD DATA WERE ABSTRACTED TO ASCERTAIN MATERNAL DEPRESSION AND ANTIDEPRESSIVE DRUG USE. DMR METHYLATION LEVELS IN UMBILICAL CORD BLOOD LEUKOCYTES WERE QUANTIFIED USING PYROSEQUENCING. FROM THE 436 NEWBORNS, LABORATORY DATA WERE OBTAINED FOR 356 INDIVIDUALS AT THE IGF2 DMRS, AND FOR 411 INDIVIDUALS AT THE H19 DMRS; ABOUT HALF OF EACH GROUP WAS AFRICAN AMERICAN OR CAUCASIAN. WHILE OVERALL NO ASSOCIATION BETWEEN DEPRESSION AND METHYLATION PROFILES WAS FOUND, WE OBSERVED A SIGNIFICANT HYPERMETHYLATION OF THE H19 DMRS IN NEWBORNS OF AFRICAN AMERICAN (N = 177) BUT NOT CAUCASIAN (N = 168) MOTHERS WHO REPORTED THE USE OF ANTIDEPRESSIVE DRUGS DURING PREGNANCY (BETA = +6.89, P = 0.01). OF NOTE, OUR DATA REVEAL A RACE-INDEPENDENT ASSOCIATION BETWEEN SMOKING DURING PREGNANCY AND METHYLATION AT THE IGF2 DMR (+3.05%, P = 0.01). IN CONCLUSION, OUR FINDINGS SUGGEST A RACE-DEPENDENT RESPONSE RELATED TO MATERNAL USE OF ANTIDEPRESSANTS AT ONE OF THE IGF2 DMRS IN THE OFFSPRING.	2011	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
7 4010  42 LOW MATERNAL ADHERENCE TO A MEDITERRANEAN DIET IS ASSOCIATED WITH INCREASE IN METHYLATION AT THE MEG3-IG DIFFERENTIALLY METHYLATED REGION IN FEMALE INFANTS. DIET IS DICTATED BY THE SURROUNDING ENVIRONMENT, AS FOOD ACCESS AND AVAILABILITY MAY CHANGE DEPENDING ON WHERE ONE LIVES. MATERNAL DIET DURING PREGNANCY IS AN IMPORTANT PART OF THE IN UTERO ENVIRONMENT, AND MAY AFFECT THE EPIGENOME. STUDIES LOOKING AT OVERALL DIET PATTERN IN RELATION TO DNA METHYLATION HAVE BEEN LACKING. THE MEDITERRANEAN DIET IS KNOWN FOR ITS HEALTH BENEFITS, INCLUDING DECREASED INFLAMMATION, WEIGHT LOSS, AND MANAGEMENT OF CHRONIC DISEASES. THIS STUDY ASSESSES THE ASSOCIATION BETWEEN MATERNAL ADHERENCE TO A MEDITERRANEAN DIET PATTERN DURING PREGNANCY AND INFANT DNA METHYLATION AT BIRTH. MEDITERRANEAN DIET ADHERENCE IN EARLY PREGNANCY WAS MEASURED IN 390 WOMEN ENROLLED IN THE NEWBORN EPIGENETIC STUDY, AND DNA METHYLATION WAS ASSESSED IN THEIR INFANTS AT BIRTH. MULTINOMIAL LOGISTIC REGRESSION WAS USED TO ASSESS THE ASSOCIATION BETWEEN ADHERENCE TO A MEDITERRANEAN DIET AND INFANT METHYLATION AT THE MEG3, MEG3-IG, PLEIOMORPHIC ADENOMA GENE-LIKE 1, INSULIN-LIKE GROWTH FACTOR 2 GENE, H19, MESODERM-SPECIFIC TRANSCRIPT, NEURONATIN, PATERNALLY EXPRESSED GENE 3, SARCOGLYCAN AND PATERNALLY EXPRESSED GENE 10 REGIONS, MEASURED BY PYROSEQUENCING. INFANTS OF MOTHERS WITH A LOW ADHERENCE TO A MEDITERRANEAN DIET HAD A GREATER ODDS OF HYPO-METHYLATION AT THE MEG3-IG DIFFERENTIALLY METHYLATED REGION (DMR). SEX-STRATIFIED MODELS SHOWED THAT THIS ASSOCIATION WAS PRESENT IN GIRLS ONLY. THIS STUDY PROVIDES EARLY EVIDENCE ON THE ASSOCIATION BETWEEN OVERALL DIET PATTERN AND METHYLATION AT THE 9 DMRS INCLUDED IN THIS STUDY, AND SUGGESTS THAT MATERNAL DIET CAN HAVE A SEX-SPECIFIC IMPACT ON INFANT DNA METHYLATION AT SPECIFIC IMPRINTED DMRS.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
8 4085  52 MATERNAL OBESITY AND GESTATIONAL DIABETES REPROGRAM THE METHYLOME OF OFFSPRING BEYOND BIRTH BY INDUCING EPIGENETIC SIGNATURES IN METABOLIC AND DEVELOPMENTAL PATHWAYS. BACKGROUND: OBESITY IS A NEGATIVE CHRONIC METABOLIC HEALTH CONDITION THAT REPRESENTS AN ADDITIONAL RISK FOR THE DEVELOPMENT OF MULTIPLE PATHOLOGIES. EPIDEMIOLOGICAL STUDIES HAVE SHOWN HOW MATERNAL OBESITY OR GESTATIONAL DIABETES MELLITUS DURING PREGNANCY CONSTITUTE SERIOUS RISK FACTORS IN RELATION TO THE APPEARANCE OF CARDIOMETABOLIC DISEASES IN THE OFFSPRING. FURTHERMORE, EPIGENETIC REMODELLING MAY HELP EXPLAIN THE MOLECULAR MECHANISMS THAT UNDERLIE THESE EPIDEMIOLOGICAL FINDINGS. THUS, IN THIS STUDY WE EXPLORED THE DNA METHYLATION LANDSCAPE OF CHILDREN BORN TO MOTHERS WITH OBESITY AND GESTATIONAL DIABETES DURING THEIR FIRST YEAR OF LIFE. METHODS: WE USED ILLUMINA INFINIUM METHYLATIONEPIC BEADCHIP ARRAYS TO PROFILE MORE THAN 770,000 GENOME-WIDE CPG SITES IN BLOOD SAMPLES FROM A PAEDIATRIC LONGITUDINAL COHORT CONSISTING OF 26 CHILDREN BORN TO MOTHERS WHO SUFFERED FROM OBESITY OR OBESITY WITH GESTATIONAL DIABETES MELLITUS DURING PREGNANCY AND 13 HEALTHY CONTROLS (MEASUREMENTS TAKEN AT 0, 6 AND 12 MONTH; TOTAL N = 90). WE CARRIED OUT CROSS-SECTIONAL AND LONGITUDINAL ANALYSES TO DERIVE DNA METHYLATION ALTERATIONS ASSOCIATED WITH DEVELOPMENTAL AND PATHOLOGY-RELATED EPIGENOMICS. RESULTS: WE IDENTIFIED ABUNDANT DNA METHYLATION CHANGES DURING CHILD DEVELOPMENT FROM BIRTH TO 6 MONTHS AND, TO A LESSER EXTENT, UP TO 12 MONTHS OF AGE. USING CROSS-SECTIONAL ANALYSES, WE DISCOVERED DNA METHYLATION BIOMARKERS MAINTAINED ACROSS THE FIRST YEAR OF LIFE THAT COULD DISCRIMINATE CHILDREN BORN TO MOTHERS WHO SUFFERED FROM OBESITY OR OBESITY WITH GESTATIONAL DIABETES. IMPORTANTLY, ENRICHMENT ANALYSES SUGGESTED THAT THESE ALTERATIONS CONSTITUTE EPIGENETIC SIGNATURES THAT AFFECT GENES AND PATHWAYS INVOLVED IN THE METABOLISM OF FATTY ACIDS, POSTNATAL DEVELOPMENTAL PROCESSES AND MITOCHONDRIAL BIOENERGETICS, SUCH AS CPT1B, SLC38A4, SLC35F3 AND FN3K. FINALLY, WE OBSERVED EVIDENCE OF AN INTERACTION BETWEEN DEVELOPMENTAL DNA METHYLATION CHANGES AND MATERNAL METABOLIC CONDITION ALTERATIONS. CONCLUSIONS: OUR OBSERVATIONS HIGHLIGHT THE FIRST SIX MONTHS OF DEVELOPMENT AS BEING THE MOST CRUCIAL FOR EPIGENETIC REMODELLING. FURTHERMORE, OUR RESULTS SUPPORT THE EXISTENCE OF SYSTEMIC INTRAUTERINE FOETAL PROGRAMMING LINKED TO OBESITY AND GESTATIONAL DIABETES THAT AFFECTS THE CHILDHOOD METHYLOME BEYOND BIRTH, WHICH INVOLVES ALTERATIONS RELATED TO METABOLIC PATHWAYS, AND WHICH MAY INTERACT WITH ORDINARY POSTNATAL DEVELOPMENT PROGRAMMES.	2023	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
9 4691  69 NEWBORNS OF OBESE PARENTS HAVE ALTERED DNA METHYLATION PATTERNS AT IMPRINTED GENES. BACKGROUND: SEVERAL EPIDEMIOLOGIC STUDIES HAVE DEMONSTRATED ASSOCIATIONS BETWEEN PERICONCEPTIONAL ENVIRONMENTAL EXPOSURES AND HEALTH STATUS OF THE OFFSPRING IN LATER LIFE. ALTHOUGH THESE ENVIRONMENTALLY RELATED EFFECTS HAVE BEEN ATTRIBUTED TO EPIGENETIC CHANGES, SUCH AS DNA METHYLATION SHIFTS AT IMPRINTED GENES, LITTLE IS KNOWN ABOUT THE POTENTIAL EFFECTS OF MATERNAL AND PATERNAL PRECONCEPTIONAL OVERNUTRITION OR OBESITY. OBJECTIVE: WE EXAMINED PARENTAL PRECONCEPTIONAL OBESITY IN RELATION TO DNA METHYLATION PROFILES AT MULTIPLE HUMAN IMPRINTED GENES IMPORTANT IN NORMAL GROWTH AND DEVELOPMENT, SUCH AS: MATERNALLY EXPRESSED GENE 3 (MEG3), MESODERM-SPECIFIC TRANSCRIPT (MEST), PATERNALLY EXPRESSED GENE 3 (PEG3), PLEIOMORPHIC ADENOMA GENE-LIKE 1 (PLAGL1), EPSILON SARCOGLYCAN AND PATERNALLY EXPRESSED GENE 10 (SGCE/PEG10) AND NEURONATIN (NNAT). METHODS: WE MEASURED METHYLATION PERCENTAGES AT THE DIFFERENTIALLY METHYLATED REGIONS (DMRS) BY BISULFITE PYROSEQUENCING IN DNA EXTRACTED FROM UMBILICAL CORD BLOOD LEUKOCYTES OF 92 NEWBORNS. PRECONCEPTIONAL OBESITY, DEFINED AS BMI ?30 KG M(-2), WAS ASCERTAINED THROUGH STANDARDIZED QUESTIONNAIRES. RESULTS: AFTER ADJUSTING FOR POTENTIAL CONFOUNDERS AND CLUSTER EFFECTS, PATERNAL OBESITY WAS SIGNIFICANTLY ASSOCIATED WITH LOWER METHYLATION LEVELS AT THE MEST (BETA=-2.57; S.E.=0.95; P=0.008), PEG3 (BETA=-1.71; S.E.=0.61; P=0.005) AND NNAT (BETA=-3.59; S.E.=1.76; P=0.04) DMRS. CHANGES RELATED TO MATERNAL OBESITY DETECTED AT OTHER LOCI WERE AS FOLLOWS: BETA-COEFFICIENT WAS +2.58 (S.E.=1.00; P=0.01) AT THE PLAGL1 DMR AND -3.42 (S.E.=1.69; P=0.04) AT THE MEG3 DMR. CONCLUSION: WE FOUND ALTERED METHYLATION OUTCOMES AT MULTIPLE IMPRINT REGULATORY REGIONS IN CHILDREN BORN TO OBESE PARENTS, COMPARED WITH CHILDREN BORN TO NON-OBESE PARENTS. IN SPITE OF THE SMALL SAMPLE SIZE, OUR DATA SUGGEST A PRECONCEPTIONAL INFLUENCE OF PARENTAL LIFE-STYLE OR OVERNUTRITION ON THE (RE)PROGRAMMING OF IMPRINT MARKS DURING GAMETOGENESIS AND EARLY DEVELOPMENT. MORE SPECIFICALLY, THE SIGNIFICANT AND INDEPENDENT ASSOCIATION BETWEEN PATERNAL OBESITY AND THE OFFSPRING'S METHYLATION STATUS SUGGESTS THE SUSCEPTIBILITY OF THE DEVELOPING SPERM FOR ENVIRONMENTAL INSULTS. THE ACQUIRED IMPRINT INSTABILITY MAY BE CARRIED ONTO THE NEXT GENERATION AND INCREASE THE RISK FOR CHRONIC DISEASES IN ADULTHOOD.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
10 4066  46 MATERNAL AND PATERNAL PERICONCEPTIONAL NUTRITION AS AN INDICATOR OF OFFSPRING METABOLIC SYNDROME RISK IN LATER LIFE THROUGH EPIGENETIC IMPRINTING: A SYSTEMATIC REVIEW. AIMS: THIS REVIEW EXAMINED WHETHER MATERNAL AND PATERNAL PERICONCEPTIONAL NUTRITION EFFECTS AN OFFSPRING'S LIKELIHOOD OF DEVELOPING CHRONIC METABOLIC RELATED CONDITIONS DUE TO EPIGENETIC IMPRINTING. METHODS: A LITERATURE SEARCH WAS CONDUCTED IN MULTIPLE SCIENCE DATABASES AND LIMITED TO STUDIES PUBLISHED AFTER 2012, IN ENGLISH LANGUAGE AND PEER REVIEWED. THE DATA FROM SELECTED ARTICLES WERE EXTRACTED AND A QUALITATIVE APPROACH WAS EMPLOYED DUE TO HETEROGENEITY OF RESULTS. RESULTS: NEWBORNS FROM OBESE FATHERS SHOWED ALTERED METHYLATION OVERALL AND SIGNIFICANT HYPOMETHYLATION AT THE INSULIN-LIKE GROWTH FACTOR 2 (IGF2) GENE. HIGH MATERNAL PRE-PREGNANCY BODY MASS INDEX (BMI) WAS ASSOCIATED WITH ALTERED OFFSPRING DNA METHYLATION LEVELS AND GESTATIONAL DIABETES MELLITUS INDUCED SIGNIFICANTLY INCREASED METHYLATION LEVELS IN OFFSPRING. GESTATIONAL WEIGHT GAIN WAS NOT ASSOCIATED WITH DIFFERENTIALLY METHYLATED CORD BLOOD. BIRTH WEIGHT WAS HIGHER IN OFFSPRING EXPOSED TO FAMINE IN EARLY GESTATION. OFFSPRING BORN POST MATERNAL BARIATRIC SURGERY SHOWED A LOWER PERCENTAGE OF BODY FAT AND IMPROVED FASTING INSULIN LEVELS COMPARED TO SIBLINGS BORN PRE-MATERNAL BARIATRIC SURGERY. CONCLUSIONS: THE AVAILABLE EVIDENCE SUGGESTS THAT POOR MATERNAL AND PATERNAL PERICONCEPTIONAL NUTRITION CAN INCREASE THE RISK OF METABOLIC SYNDROME IN OFFSPRING, THROUGH EPIGENETIC IMPRINTING. POTENTIAL PARENTS SHOULD BE ADVISED THAT MAINTAINING A HEALTHY DIET AND BMI IS LIKELY TO REDUCE THE RISK OF METABOLIC SYNDROME IN OFFSPRING.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
11 1439  47 DIFFERENTIAL PLACENTAL CPG METHYLATION IS ASSOCIATED WITH CHRONIC LUNG DISEASE OF PREMATURITY. BACKGROUND: CHRONIC LUNG DISEASE (CLD) IS THE MOST COMMON PULMONARY MORBIDITY IN EXTREMELY PRETERM INFANTS. IT IS UNCLEAR TO WHAT EXTENT PRENATAL EXPOSURES INFLUENCE THE RISK OF CLD. EPIGENETIC VARIATION IN PLACENTA DNA METHYLATION MAY BE ASSOCIATED WITH DIFFERENTIAL RISK OF CLD, AND THESE ASSOCIATIONS MAY BE DEPENDENT UPON SEX. METHODS: DATA WERE OBTAINED FROM A MULTI-CENTER COHORT OF INFANTS BORN EXTREMELY PRETERM (<28 WEEKS' GESTATION) AND AN EPIGENOME-WIDE APPROACH WAS USED TO IDENTIFY ASSOCIATIONS BETWEEN PLACENTAL DNA METHYLATION AND CLD (N = 423). ASSOCIATIONS WERE EVALUATED USING ROBUST LINEAR REGRESSION ADJUSTING FOR COVARIATES, WITH A FALSE DISCOVERY RATE OF 0.05. ANALYSES STRATIFIED BY SEX WERE USED TO ASSESS DIFFERENCES IN METHYLATION-CLD ASSOCIATIONS. RESULTS: CLD WAS ASSOCIATED WITH DIFFERENTIAL METHYLATION AT 49 CPG SITES REPRESENTING 46 GENES IN THE PLACENTA. CLD WAS ASSOCIATED WITH DIFFERENTIAL METHYLATION OF PROBES WITHIN GENES RELATED TO PATHWAYS INVOLVED IN FETAL LUNG DEVELOPMENT, SUCH AS P53 SIGNALING AND MYO-INOSITOL BIOSYNTHESIS. ASSOCIATIONS BETWEEN CPG METHYLATION AND CLD DIFFERED BY SEX. CONCLUSIONS: DIFFERENTIAL PLACENTAL METHYLATION WITHIN GENES WITH KEY ROLES IN FETAL LUNG DEVELOPMENT MAY REFLECT COMPLEX CELL SIGNALING BETWEEN THE PLACENTA AND FETUS WHICH MEDIATE CLD RISK. THESE PATHWAYS APPEAR TO BE DISTINCT BASED ON FETAL SEX. IMPACT: IN EXTREMELY PRETERM INFANTS, DIFFERENTIAL METHYLATION OF CPG SITES WITHIN PLACENTAL GENES INVOLVED IN PATHWAYS RELATED TO CELL SIGNALING, OXIDATIVE STRESS, AND TROPHOBLAST INVASION IS ASSOCIATED WITH CHRONIC LUNG DISEASE OF PREMATURITY. DNA METHYLATION PATTERNS ASSOCIATED WITH CHRONIC LUNG DISEASE WERE DISTINCTLY BASED ON FETAL SEX, SUGGESTING A POTENTIAL MECHANISM UNDERLYING DIMORPHIC PHENOTYPES. MECHANISMS RELATED TO FETAL HYPOXIA AND PLACENTAL MYO-INOSITOL SIGNALING MAY PLAY A ROLE IN FETAL LUNG PROGRAMMING AND THE DEVELOPMENTAL ORIGINS OF CHRONIC LUNG DISEASE. CONTINUED RESEARCH OF THE RELATIONSHIP BETWEEN THE PLACENTAL EPIGENOME AND CHRONIC LUNG DISEASE COULD INFORM EFFORTS TO AMELIORATE OR PREVENT THIS CONDITION.	2022	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
12 5192  39 PRENATAL ENVIRONMENTAL STRESSORS AND DNA METHYLATION LEVELS IN PLACENTA AND PERIPHERAL TISSUES OF MOTHERS AND NEONATES EVALUATED BY APPLYING ARTIFICIAL NEURAL NETWORKS. EXPOSURE TO ENVIRONMENTAL STRESSORS DURING PREGNANCY PLAYS AN IMPORTANT ROLE IN INFLUENCING SUBSEQUENT SUSCEPTIBILITY TO CERTAIN CHRONIC DISEASES THROUGH THE MODULATION OF EPIGENETIC MECHANISMS, INCLUDING DNA METHYLATION. OUR AIM WAS TO EXPLORE THE CONNECTIONS BETWEEN ENVIRONMENTAL EXPOSURES DURING GESTATION WITH DNA METHYLATION OF PLACENTAL CELLS, MATERNAL AND NEONATAL BUCCAL CELLS BY APPLYING ARTIFICIAL NEURAL NETWORKS (ANNS). A TOTAL OF 28 MOTHER-INFANT PAIRS WERE ENROLLED. DATA ON GESTATIONAL EXPOSURE TO ADVERSE ENVIRONMENTAL FACTORS AND ON MOTHER HEALTH STATUS WERE COLLECTED THROUGH THE ADMINISTRATION OF A QUESTIONNAIRE. DNA METHYLATION ANALYSES AT BOTH GENE-SPECIFIC AND GLOBAL LEVEL WERE ANALYZED IN PLACENTAS, MATERNAL AND NEONATAL BUCCAL CELLS. IN THE PLACENTA, THE CONCENTRATIONS OF VARIOUS METALS AND DIOXINS WERE ALSO ANALYZED. ANALYSIS OF ANNS REVEALED THAT SUBOPTIMAL BIRTH WEIGHT IS ASSOCIATED WITH PLACENTAL H19 METHYLATION, MATERNAL STRESS DURING PREGNANCY WITH METHYLATION LEVELS OF NR3C1 AND BDNF IN PLACENTAS AND MOTHER'S BUCCAL DNA, RESPECTIVELY, AND EXPOSURE TO AIR POLLUTANTS WITH MATERNAL MGMT METHYLATION. ASSOCIATIONS WERE ALSO OBSERVED BETWEEN PLACENTAL CONCENTRATIONS OF LEAD, CHROMIUM, CADMIUM AND MERCURY WITH METHYLATION LEVELS OF OXTR IN PLACENTAS, HSD11B2 IN MATERNAL BUCCAL CELLS AND PLACENTAS, MECP2 IN NEONATAL BUCCAL CELLS, AND MTHFR IN MATERNAL BUCCAL CELLS. FURTHERMORE, DIOXIN CONCENTRATIONS WERE ASSOCIATED WITH PLACENTAL RELN, NEONATAL HSD11B2 AND MATERNAL H19 GENE METHYLATION LEVELS. CURRENT RESULTS SUGGEST THAT EXPOSURE OF PREGNANT WOMEN TO ENVIRONMENTAL STRESSORS DURING PREGNANCY COULD INDUCE ABERRANT METHYLATION LEVELS IN GENES LINKED TO SEVERAL PATHWAYS IMPORTANT FOR EMBRYOGENESIS IN BOTH THE PLACENTA, POTENTIALLY AFFECTING FOETAL DEVELOPMENT, AND IN THE PERIPHERAL TISSUES OF MOTHERS AND INFANTS, POTENTIALLY PROVIDING PERIPHERAL BIOMARKERS OF ENVIRONMENTAL EXPOSURE.	2023	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
13 1503  54 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 5748  41 SOCIAL AND PHYSICAL ENVIRONMENTS EARLY IN DEVELOPMENT PREDICT DNA METHYLATION OF INFLAMMATORY GENES IN YOUNG ADULTHOOD. CHRONIC INFLAMMATION CONTRIBUTES TO A WIDE RANGE OF HUMAN DISEASES, AND ENVIRONMENTS IN INFANCY AND CHILDHOOD ARE IMPORTANT DETERMINANTS OF INFLAMMATORY PHENOTYPES. THE UNDERLYING BIOLOGICAL MECHANISMS CONNECTING EARLY ENVIRONMENTS WITH THE REGULATION OF INFLAMMATION IN ADULTHOOD ARE NOT KNOWN, BUT EPIGENETIC PROCESSES ARE PLAUSIBLE CANDIDATES. WE TESTED THE HYPOTHESIS THAT PATTERNS OF DNA METHYLATION (DNAM) IN INFLAMMATORY GENES IN YOUNG ADULTHOOD WOULD BE PREDICTED BY EARLY LIFE NUTRITIONAL, MICROBIAL, AND PSYCHOSOCIAL EXPOSURES PREVIOUSLY ASSOCIATED WITH LEVELS OF INFLAMMATION. DATA COME FROM A POPULATION-BASED LONGITUDINAL BIRTH COHORT STUDY IN METROPOLITAN CEBU, THE PHILIPPINES, AND DNAM WAS CHARACTERIZED IN WHOLE BLOOD SAMPLES FROM 494 PARTICIPANTS (AGE 20-22 Y). ANALYSES FOCUSED ON PROBES IN 114 TARGET GENES INVOLVED IN THE REGULATION OF INFLAMMATION, AND WE IDENTIFIED 10 SITES ACROSS NINE GENES WHERE THE LEVEL OF DNAM WAS SIGNIFICANTLY PREDICTED BY THE FOLLOWING VARIABLES: HOUSEHOLD SOCIOECONOMIC STATUS IN CHILDHOOD, EXTENDED ABSENCE OF A PARENT IN CHILDHOOD, EXPOSURE TO ANIMAL FECES IN INFANCY, BIRTH IN THE DRY SEASON, OR DURATION OF EXCLUSIVE BREASTFEEDING. TO EVALUATE THE BIOLOGICAL SIGNIFICANCE OF THESE SITES, WE TESTED FOR ASSOCIATIONS WITH A PANEL OF INFLAMMATORY BIOMARKERS MEASURED IN PLASMA OBTAINED AT THE SAME AGE AS DNAM ASSESSMENT. THREE SITES PREDICTED ELEVATED INFLAMMATION, AND ONE SITE PREDICTED LOWER INFLAMMATION, CONSISTENT WITH THE INTERPRETATION THAT LEVELS OF DNAM AT THESE SITES ARE FUNCTIONALLY RELEVANT. THIS PATTERN OF RESULTS POINTS TOWARD DNAM AS A POTENTIALLY IMPORTANT BIOLOGICAL MECHANISM THROUGH WHICH DEVELOPMENTAL ENVIRONMENTS SHAPE INFLAMMATORY PHENOTYPES ACROSS THE LIFE COURSE.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
15 1573  49 DNA METHYLATION PATTERNS IN NEWBORNS EXPOSED TO TOBACCO IN UTERO. BACKGROUND: MATERNAL SMOKING DURING PREGNANCY IS A MAJOR RISK FACTOR FOR ADVERSE HEALTH OUTCOMES. THE MAIN OBJECTIVE OF THE STUDY WAS TO ASSESS THE IMPACT OF IN UTERO TOBACCO EXPOSURE ON DNA METHYLATION IN CHILDREN BORN AT TERM WITH APPROPRIATE WEIGHT AT BIRTH. METHODS: TWENTY MOTHER-NEWBORN DYADS, AFTER UNCOMPLICATED PREGNANCIES, IN THE ABSENCE OF PERINATAL ILLNESS WERE INCLUDED. ALL MOTHERS WERE HEALTHY WITH NO CARDIOVASCULAR RISK FACTORS, EXCEPT FOR THE ASSOCIATED RISKS AMONG THOSE MOTHERS WHO SMOKED. UMBILICAL CORD BLOOD AND MATERNAL PERIPHERAL VENOUS BLOOD WERE COLLECTED AND AN EPIGENOME-WIDE ASSOCIATION STUDY WAS PERFORMED USING A 450 K EPIGENOME-WIDE SCAN (ILLUMINA INFINIUM HUMANMETHYLATION 450BEADCHIP) WITH ADJUSTMENT TO NORMALIZE THE DNA METHYLATION FOR DATA CELL VARIABILITY IN WHOLE BLOOD. RESULTS: THE MATERNAL PLASMATIC COTININE LEVELS RANGED FROM 10.70-115.40 NG/ML IN THE EXPOSED GROUP TO 0-0.59 NG/ML IN THE NON-EXPOSED GROUP. AFTER ADJUSTING FOR MULTIPLE COMPARISONS IN 427102 PROBES, STATISTICALLY SIGNIFICANT DIFFERENCES FOR 31 CPG SITES, ASSOCIATED TO 25 GENES WERE OBSERVED. THERE WAS A GREATER THAN EXPECTED PROPORTION OF STATISTICALLY-SIGNIFICANT LOCI LOCATED IN CPG ISLANDS (FISHER'S EXACT TEST, P = 0.029) AND OF THOSE CPG ISLANDS, 90.3% EXHIBIT HIGHER METHYLATION LEVELS IN THE EXPOSED GROUP. THE MOST STRIKING AND SIGNIFICANT CPG SITE, CG05727225, IS LOCATED IN THE CHROMOSOME 11P15.4, WITHIN THE ADRENOMEDULLIN GENE. CONCLUSIONS: IN UTERO TOBACCO EXPOSURE, EVEN IN THE ABSENCE OF FETAL GROWTH RESTRICTION, MAY ALTER THE EPIGENOME, CONTRIBUTING TO GLOBAL DNA HYPOMETHYLATION. THEREFORE, DNA STATUS CAN BE USED AS A BIOMARKER OF PRENATAL INSULTS. CONSIDERING THE POSSIBILITY TO REVERSE EPIGENETIC MODIFICATIONS, A WINDOW OF OPPORTUNITY EXISTS TO CHANGE THE PROGRAMMED CHRONIC DISEASE.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
16 5093  58 PLACENTAS FROM PREGNANCIES CONCEIVED BY IVF/ICSI HAVE A REDUCED DNA METHYLATION LEVEL AT THE H19 AND MEST DIFFERENTIALLY METHYLATED REGIONS. STUDY QUESTION: DOES IVF/ICSI HAVE AN EFFECT ON THE EPIGENETIC REGULATION OF THE HUMAN PLACENTA? SUMMARY ANSWER: WE FOUND A REDUCED DNA METHYLATION LEVEL AT THE H19 AND MEST DIFFERENTIALLY METHYLATED REGIONS (DMRS), AND AN INCREASED RNA EXPRESSION OF H19 IN PLACENTAS FROM PREGNANCIES CONCEIVED BY IVF/ICSI WHEN COMPARED WITH PLACENTAS FROM SPONTANEOUS CONCEPTION. WHAT IS KNOWN ALREADY: CHANGES IN FETAL ENVIRONMENT ARE ASSOCIATED WITH ADVERSE HEALTH OUTCOMES. THE PLACENTA IS PIVOTAL FOR INTRAUTERINE ENVIRONMENT. ANIMAL STUDIES SHOW THAT EPIGENETIC REGULATION PLAYS AN IMPORTANT ROLE IN THESE ENVIRONMENT-INDUCED PHENOTYPIC EFFECTS. ALSO, THE PREIMPLANTATION EMBRYO ENVIRONMENT AFFECTS BIRTHWEIGHT AS WELL AS THE RISK OF CHRONIC ADULT DISEASES. EPIGENETIC PROCESSES ARE SENSITIVE TO THE ENVIRONMENT, ESPECIALLY DURING THE PERIOD AROUND CONCEPTION. STUDY DESIGN AND PARTICIPANTS: PLACENTAL TISSUE WAS COLLECTED FROM 35 SPONTANEOUSLY CONCEIVED PREGNANCIES AND 35 IVF/ICSI (5 IVF, 30 ICSI) DERIVED PREGNANCIES. WE QUANTITATIVELY ANALYSED THE DNA METHYLATION PATTERNS OF A NUMBER OF CONSECUTIVE CPGS IN THE CORE REGIONS OF DMRS AND OTHER REGULATORY REGIONS OF IMPRINTED GENES, SINCE THESE ARE INVOLVED IN PLACENTAL AND FETAL GROWTH AND DEVELOPMENT. METHODS: BY USING PYROSEQUENCING, THE DNA METHYLATION AT SEVEN GERMLINE-DERIVED PRIMARY DMRS WAS ANALYSED QUANTITATIVELY. FIVE OF THESE ARE MATERNALLY METHYLATED (MEST ISOFORM ALPHA AND BETA, PEG3, KCNQ1OT1 AND SNRPN) AND TWO ARE PATERNALLY METHYLATED [H19 DMR AND THE INTERGENIC REGION BETWEEN DLK1 AND MEG3 (IG-DMR)]. THE POST-FERTILIZATION-DERIVED SECONDARY DMRS, IGF2 (DMR0 AND 2) AND IG-DMR (CG7, ALSO CALLED MEG3 DMR), AND THE MEG3 PROMOTER REGION WERE EXAMINED AS WELL. IN CASE OF DIFFERENTIAL METHYLATION BETWEEN THE TWO GROUPS, THE EFFECT ON GENE EXPRESSION WAS ASSESSED BY QUANTITATIVE REAL-TIME PCR. MAIN RESULTS AND THE ROLE OF CHANCE: BOTH THE PROMOTER REGION OF MEST ISOFORM ALPHA AND BETA AND THE 6TH CTCF BINDING SITE WITHIN THE H19 DMR WERE SIGNIFICANTLY HYPOMETHYLATED IN THE IVF/ICSI GROUP. THE PHENOMENON WAS CONSISTENTLY OBSERVED OVER ALL CPG SITES ANALYSED AND NOT RESTRICTED TO SINGLE CPG SITES. THE OTHER PRIMARY AND SECONDARY DMRS WERE NOT AFFECTED. EXPRESSION OF H19 WAS INCREASED IN THE IVF/ICSI GROUP, WHILE THAT OF IGF2 AND MEST REMAINED SIMILAR. LIMITATIONS, REASONS FOR CAUTION: IN THE IVF/ICSI GROUP, MOSTLY ICSI PREGNANCIES WERE INVESTIGATED. THE ICSI TECHNIQUE OR MALE SUBFERTILITY COULD BE A CONFOUNDING FACTOR. THEREFORE, OUR RESULTS ARE LESS GENERALIZABLE TO IVF PREGNANCIES. WIDER IMPLICATIONS OF THE FINDINGS: THE CLINICAL EFFECTS OF THE OBSERVED PLACENTAL HYPOMETHYLATIONS ON THE DEVELOPMENTAL PROGRAMMING OF THE IVF/ICSI PROGENY, IF ANY, ARE AS YET UNKNOWN. WHETHER THE HYPOMETHYLATION IS AN ADAPTATION OF THE PLACENTA TO MAINTAIN FETAL SUPPLY AND AMELIORATE THE EFFECTS OF ENVIRONMENTAL CUES, OR WHETHER IT IS A DEREGULATION LEADING TO DERANGED DEVELOPMENTAL PROGRAMMING WITH OR WITHOUT INCREASED VULNERABILITY FOR DISEASE, CONSISTENT WITH THE DEVELOPMENTAL ORIGINS OF HEALTH AND DISEASE HYPOTHESIS, NEEDS FURTHER INVESTIGATION. STUDY FUNDING/COMPETING INTEREST(S): PARTLY FUNDED BY AN UNRESTRICTED RESEARCH GRANT BY ORGANON BV (NOW MSD BV) WITHOUT ANY ROLE IN STUDY DESIGN, DATA COLLECTION AND ANALYSIS, OR PREPARATION OF THE MANUSCRIPT. NO CONFLICT OF INTERESTS TO DECLARE. TRIAL REGISTRATION NUMBER: DUTCH TRIAL REGISTRY (NTR) NUMBER 1298.	2013	

17 4072  41 MATERNAL DNA METHYLATION SIGNATURES OF ARSENIC EXPOSURE IS ASSOCIATED WITH ADULT OFFSPRING INSULIN RESISTANCE IN THE STRONG HEART STUDY. EXPOSURE TO LOW TO MODERATE ARSENIC (AS) LEVELS HAS BEEN ASSOCIATED WITH TYPE 2 DIABETES (T2D) AND OTHER CHRONIC DISEASES IN AMERICAN INDIAN COMMUNITIES. PRENATAL EXPOSURE TO AS MAY ALSO INCREASE THE RISK FOR T2D IN ADULTHOOD, AND MATERNAL AS HAS BEEN ASSOCIATED WITH ADULT OFFSPRING METABOLIC HEALTH MEASUREMENTS. WE HYPOTHESIZED THAT T2D-RELATED OUTCOMES IN ADULT OFFSPRING BORN TO WOMEN EXPOSED TO LOW TO MODERATE AS CAN BE EVALUATED UTILIZING A MATERNALLY-DERIVED MOLECULAR BIOSIGNATURE OF AS EXPOSURE. HEREIN, WE EVALUATED THE ASSOCIATION OF MATERNAL DNA METHYLATION WITH INCIDENT T2D AND INSULIN RESISTANCE (HOMEOSTATIC MODEL ASSESSMENT OF INSULIN RESISTANCE [HOMA2-IR]) IN ADULT OFFSPRING. FOR DNA METHYLATION, WE USED 20 DIFFERENTIALLY METHYLATED CYTOSINE-GUANINE DINUCLEOTIDES (CPG) PREVIOUSLY ASSOCIATED WITH THE SUM OF INORGANIC AND METHYLATED AS SPECIES (SIGMAAS) IN URINE IN THE STRONG HEART STUDY (SHS). OF THESE 20 CPGS, WE FOUND SIX CPGS NOMINALLY ASSOCIATED (P < 0.05) WITH HOMA2-IR IN A FULLY ADJUSTED MODEL THAT INCLUDED CLINICALLY RELEVANT COVARIATES AND OFFSPRING ADIPOSITY MEASUREMENTS; A SIMILAR MODEL THAT ADJUSTED INSTEAD FOR MATERNAL ADIPOSITY MEASUREMENTS FOUND THREE CPGS NOMINALLY ASSOCIATED WITH HOMA2-IR, TWO OF WHICH OVERLAPPED THE OFFSPRING ADIPOSITY MODEL. AFTER ADJUSTING FOR MULTIPLE COMPARISONS, CG03036214 REMAINED ASSOCIATED WITH HOMA2-IR (Q < 0.10) IN THE OFFSPRING ADIPOSITY MODEL. THE ODDS RATIO OF INCIDENT T2D INCREASED WITH AN INCREASE IN MATERNAL DNA METHYLATION AT ONE HOMA2-IR ASSOCIATED CPG IN THE MODEL ADJUSTING FOR OFFSPRING ADIPOSITY, CG12116137, WHEREAS ADJUSTING FOR MATERNAL ADIPOSITY HAD A MINIMAL EFFECT ON THE ASSOCIATION. OUR DATA SUGGESTS OFFSPRING ADIPOSITY, RATHER THAN MATERNAL ADIPOSITY, POTENTIALLY INFLUENCES THE EFFECTS OF MATERNAL DNAM SIGNATURES ON OFFSPRING METABOLIC HEALTH PARAMETERS. HERE, WE HAVE PRESENTED EVIDENCE SUPPORTING A ROLE FOR EPIGENETIC BIOSIGNATURES OF MATERNAL AS EXPOSURE AS A POTENTIAL BIOMARKER FOR EVALUATING RISK OF T2D-RELATED OUTCOMES IN OFFSPRING LATER IN LIFE.	2023	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
18 1553  41 DNA METHYLATION LEVELS ASSOCIATED WITH RACE AND CHILDHOOD ASTHMA SEVERITY. OBJECTIVE: ASTHMA IS A COMMON CHRONIC CHILDHOOD DISEASE WORLDWIDE. SOCIOECONOMIC STATUS, GENETIC PREDISPOSITION AND ENVIRONMENTAL FACTORS CONTRIBUTE TO ITS INCIDENCE AND SEVERITY. A DISPROPORTIONATE NUMBER OF CHILDREN WITH ASTHMA ARE ECONOMICALLY DISADVANTAGED AND LIVE IN SUBSTANDARD HOUSING WITH POTENTIAL INDOOR ENVIRONMENTAL EXPOSURES SUCH AS COCKROACHES, DUST MITES, RODENTS AND MOLDS. THESE EXPOSURES MAY MANIFEST THROUGH EPIGENETIC MECHANISMS THAT CAN LEAD TO CHANGES IN RELEVANT GENE EXPRESSION. WE EXAMINED THE ASSOCIATION OF GLOBAL DNA METHYLATION LEVELS WITH SOCIOECONOMIC STATUS, ASTHMA SEVERITY AND RACE/ETHNICITY. METHODS: WE MEASURED GLOBAL DNA METHYLATION IN PERIPHERAL BLOOD OF CHILDREN WITH ASTHMA ENROLLED IN THE KANSAS CITY SAFE AND HEALTHY HOMES PROGRAM. INCLUSION CRITERIA INCLUDED RESIDING IN THE SAME HOME FOR A MINIMUM OF 4 DAYS PER WEEK AND TOTAL FAMILY INCOME OF LESS THAN 80% OF THE KANSAS CITY MEDIAN FAMILY INCOME. DNA METHYLATION LEVELS WERE QUANTIFIED BY AN IMMUNOASSAY THAT ASSESSED THE PERCENTAGE OF 5-METHYLCYTOSINE. RESULTS: OUR RESULTS INDICATE THAT OVERALL, AFRICAN AMERICAN CHILDREN HAD HIGHER LEVELS OF GLOBAL DNA METHYLATION THAN CHILDREN OF OTHER RACES/ETHNICITIES (P = 0.029). THIS DIFFERENCE WAS MORE PRONOUNCED WHEN SOCIOECONOMIC STATUS AND ASTHMA SEVERITY WERE COUPLED WITH RACE/ETHNICITY (P = 0.042) WHERE LOW-INCOME, AFRICAN AMERICAN CHILDREN WITH PERSISTENT ASTHMA HAD SIGNIFICANTLY ELEVATED METHYLATION LEVELS RELATIVE TO OTHER RACES/ETHNICITIES IN THE SAME CONTEXT (P = 0.006, HEDGES G = 1.14). CONCLUSION: OUR STUDY DEMONSTRATES A SIGNIFICANT INTERACTION EFFECT AMONG GLOBAL DNA METHYLATION LEVELS, ASTHMA SEVERITY, RACE/ETHNICITY, AND SOCIOECONOMIC STATUS.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
19 1563  43 DNA METHYLATION OF METHYLATION COMPLEX GENES IN RELATION TO STRESS AND GENOME-WIDE METHYLATION IN MOTHER-NEWBORN DYADS. OBJECTIVES: EARLY LIFE STRESS IS KNOWN TO HAVE ENDURING BIOLOGICAL EFFECTS, PARTICULARLY WITH RESPECT TO HEALTH. EPIGENETIC MODIFICATIONS, SUCH AS DNA METHYLATION, ARE A POSSIBLE MECHANISM TO MEDIATE THE BIOLOGICAL EFFECT OF STRESS. WE PREVIOUSLY FOUND CORRELATIONS BETWEEN MATERNAL STRESS, NEWBORN BIRTHWEIGHT, AND GENOME-WIDE MEASURES OF DNA METHYLATION. HERE WE INVESTIGATE TEN GENES RELATED TO THE METHYLATION/DEMETHYLATION COMPLEX IN ORDER TO BETTER UNDERSTAND THE IMPACT OF STRESS ON HEALTH. MATERIALS AND METHODS: DNA METHYLATION AND GENETIC VARIANTS AT METHYLATION/DEMETHYLATION GENES WERE ASSAYED. MEAN METHYLATION MEASURES WERE CONSTRUCTED FOR EACH GENE AND TESTED, IN ADDITION TO GENETIC VARIANTS, FOR ASSOCIATION WITH MATERNAL STRESS MEASURES BASED ON INTERVIEW AND SURVEY DATA (CHRONIC STRESS AND WAR TRAUMA), MATERNAL VENOUS, AND NEWBORN CORD GENOME-WIDE MEAN METHYLATION (GMM), AND BIRTHWEIGHT. RESULTS: AFTER CELL TYPE CORRECTION, WE FOUND MULTIPLE PAIRWISE ASSOCIATIONS BETWEEN WAR TRAUMA, MATERNAL GMM, MATERNAL METHYLATION AT DNMT1, DNMT3A, TET3, AND MBD2, AND BIRTHWEIGHT. CONCLUSIONS: THE ASSOCIATION OF MATERNAL GMM AND MATERNAL METHYLATION AT DNMT1, DNMT3A, TET3, AND MBD2 IS CONSISTENT WITH THE ROLE OF THESE GENES IN ESTABLISHING, MAINTAINING AND ALTERING GENOME-WIDE METHYLATION PATTERNS, IN SOME CASES IN RESPONSE TO STRESS. DNMT1 PRODUCES ONE OF THE PRIMARY ENZYMES THAT REPRODUCES METHYLATION PATTERNS DURING DNA REPLICATION. DNMT3A AND TET3 HAVE BEEN IMPLICATED IN GENOME-WIDE HYPOMETHYLATION IN RESPONSE TO GLUCOCORTICOID HORMONES. ALTHOUGH WE CANNOT DETERMINE THE DIRECTIONALITY OF THE GENIC AND GENOME-WIDE CHANGES IN METHYLATION, OUR RESULTS SUGGEST THAT ALTERED METHYLATION OF SPECIFIC METHYLATION GENES MAY BE PART OF THE MOLECULAR MECHANISM UNDERLYING THE HUMAN BIOLOGICAL RESPONSE TO STRESS.	2018	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
20 1595  40 DNA METHYLATION PROVIDES INSIGHT INTO INTERGENERATIONAL RISK FOR PRETERM BIRTH IN AFRICAN AMERICANS. AFRICAN AMERICANS ARE AT INCREASED RISK FOR SPONTANEOUS PRETERM BIRTH (PTB). THOUGH PTB IS HERITABLE, GENETIC STUDIES HAVE NOT IDENTIFIED VARIANTS THAT ACCOUNT FOR ITS INTERGENERATIONAL RISK, PROMPTING THE HYPOTHESIS THAT EPIGENETIC FACTORS MAY ALSO CONTRIBUTE. THE OBJECTIVE OF THIS STUDY WAS TO EVALUATE DNA METHYLATION FROM MATERNAL LEUKOCYTES TO IDENTIFY PATTERNS SPECIFIC TO PTB AND ITS INTERGENERATIONAL RISK. DNA FROM PERIPHERAL LEUKOCYTES FROM AFRICAN AMERICAN WOMEN THAT DELIVERED PRETERM (24-34 WEEKS; N = 16) OR AT TERM (39-41 WEEKS; N = 24) WAS ASSESSED FOR DNA METHYLATION USING THE HUMANMETHYLATION450 BEADCHIP. IN MATERNAL SAMPLES, 17,829 CPG SITES ASSOCIATED WITH PTB, BUT NO CPG SITE REMAINED ASSOCIATED AFTER CORRECTION FOR MULTIPLE COMPARISONS. EXAMINATION OF PAIRED MATERNAL-FETAL SAMPLES IDENTIFIED 5,171 CPG SITES IN WHICH METHYLATION OF MATERNAL SAMPLES CORRELATED WITH METHYLATION OF HER RESPECTIVE FETUS (FDR < 0.05). THESE CORRELATED SITES WERE ENRICHED FOR ASSOCIATION WITH PTB IN MATERNAL LEUKOCYTES. THE MAJORITY OF CORRELATED CPG SITES COULD BE ATTRIBUTED TO ONE OR MORE GENETIC VARIANTS. THEY WERE ALSO SIGNIFICANTLY MORE LIKELY TO BE IN GENES INVOLVED IN METABOLIC, CARDIOVASCULAR, AND IMMUNE PATHWAYS, SUGGESTING A ROLE FOR GENETIC AND ENVIRONMENTAL CONTRIBUTIONS TO PTB RISK AND CHRONIC DISEASE. THE RESULTS OF THIS STUDY MAY PROVIDE INSIGHT INTO THE FACTORS UNDERLYING INTERGENERATIONAL RISK FOR PTB AND ITS CONSEQUENCES.	2015