title: Quantitative methylation analysis of developmentally important genes in human pregnancy losses after ART and spontaneous conception.
abstract: To study possible effects of assisted reproductive technologies (ART) on epigenetic reprogramming, we have analyzed the DNA methylation levels of differentially methylated regions (DMRs) of seven imprinted genes (H19, MEG3, LIT1, MEST, NESP55, PEG3 and SNRPN) as well as the promoter regions of the pluripotency gene NANOG and the tumor suppressor gene APC in chorionic villus samples (CVS) of 42 spontaneous miscarriages and stillbirths after ART and 29 abortions/stillbirths after spontaneous conception. We did not find an increased rate of faulty methylation patterns after ART, but significant and trend differences (ROC curve analysis, Wilcoxon test) in the methylation levels of LIT1 (P = 0.006) and H19 (P = 0.085) between ART and non-ART samples. With the possible exception of NANOG, we did not observe a gestational age effect on the methylation levels of the studied genes. The frequency of extreme methylation values in PEG3 and APC was markedly higher than in the other studied genes, indicating an increased susceptibility of some genes to epigenetic alterations. Most methylation abnormalities in CVS represented either hypermethylated DMRs of paternally and maternally imprinted genes or hypomethylated promoters of non-imprinted genes. The observed methylation abnormalities (mosaicism) are consistent with methylation reprogramming defects during early embryogenesis.
authors.affiliation: Institute of Human Genetics, Johannes Gutenberg University, 55101 Mainz, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Zechner
authors.forename: Galyna
authors.initials: G
authors.lastname: Pliushch
authors.forename: Eberhard
authors.initials: E
authors.lastname: Schneider
authors.forename: Nady
authors.initials: N
authors.lastname: El Hajj
authors.forename: Achim
authors.initials: A
authors.lastname: Tresch
authors.forename: Yoel
authors.initials: Y
authors.lastname: Shufaro
authors.forename: Larissa
authors.initials: L
authors.lastname: Seidmann
authors.forename: Wiltrud
authors.initials: W
authors.lastname: Coerdt
authors.forename: Annette M
authors.initials: AM
authors.lastname: Müller
authors.forename: Thomas
authors.initials: T
authors.lastname: Haaf
mesh_terms: D000022:Abortion, Spontaneous / Q000235:genetics*; D000328:Adult; D019175:DNA Methylation; D005260:Female; D018507:Gene Expression Regulation, Developmental; D017491:Genes, APC; D020022:Genetic Predisposition to Disease; D005858:Germany; D005865:Gestational Age; D006801:Humans; D007557:Israel; D051741:Kruppel-Like Transcription Factors / Q000235:genetics; D016014:Linear Models; D008423:Maternal Age; D008875:Middle Aged; D009030:Mosaicism; D010641:Phenotype; D011247:Pregnancy; D027724:Reproductive Techniques, Assisted / Q000009:adverse effects*; D018570:Risk Assessment; D012307:Risk Factors; D050497:Stillbirth / Q000235:genetics*; D055815:Young Adult
chemical_list: D051741:Kruppel-Like Transcription Factors; C490820:PEG3 protein, human