Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada.
Centre for Computational Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada.
Hum Mol Genet. 2019 Feb 1;28(3):372-385. doi: 10.1093/hmg/ddy321.
Children conceived using Assisted Reproductive Technologies (ART) have a higher incidence of growth and birth defects, attributable in part to epigenetic perturbations. Both ART and germline defects associated with parental infertility could interfere with epigenetic reprogramming events in germ cells or early embryos. Mouse models indicate that the placenta is more susceptible to the induction of epigenetic abnormalities than the embryo, and thus the placental methylome may provide a sensitive indicator of 'at risk' conceptuses. Our goal was to use genome-wide profiling to examine the extent of epigenetic abnormalities in matched placentas from an ART/infertility group and control singleton pregnancies (n = 44/group) from a human prospective longitudinal birth cohort, the Design, Develop, Discover (3D) Study. Principal component analysis revealed a group of ART outliers. The ART outlier group was enriched for females and a subset of placentas showing loss of methylation of several imprinted genes including GNAS, SGCE, KCNQT1OT1 and BLCAP/NNAT. Within the ART group, placentas from pregnancies conceived with in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) showed distinct epigenetic profiles as compared to those conceived with less invasive procedures (ovulation induction, intrauterine insemination). Male factor infertility and paternal age further differentiated the IVF/ICSI group, suggesting an interaction of infertility and techniques in perturbing the placental epigenome. Together, the results suggest that the human placenta is sensitive to the induction of epigenetic defects by ART and/or infertility, and we stress the importance of considering both sex and paternal factors and that some but not all ART conceptuses will be susceptible.
使用辅助生殖技术(ART)孕育的儿童生长和出生缺陷的发生率更高,部分原因是表观遗传干扰。ART 和与父母不孕相关的种系缺陷都可能干扰生殖细胞或早期胚胎中的表观遗传重编程事件。小鼠模型表明,胎盘比胚胎更容易受到表观遗传异常的诱导,因此胎盘甲基化组可能为“高危”胚胎提供敏感的指标。我们的目标是使用全基因组分析来检查来自辅助生殖/不孕组和对照单胎妊娠(每组 n=44)的匹配胎盘的表观遗传异常程度,这是一个来自人类前瞻性纵向出生队列 Design,Develop,Discover(3D)研究的。主成分分析显示出一组 ART 异常值。ART 异常值组中女性比例较高,并且有一部分胎盘表现出几个印迹基因(包括 GNAS、SGCE、KCNQT1OT1 和 BLCAP/NNAT)的甲基化丧失。在 ART 组中,与使用侵入性较小的程序(排卵诱导、宫腔内人工授精)相比,体外受精(IVF)/胞浆内精子注射(ICSI)受孕的胎盘表现出独特的表观遗传特征。男性因素不孕和父亲年龄进一步区分了 IVF/ICSI 组,表明不孕和技术在干扰胎盘表观基因组方面存在相互作用。总之,这些结果表明,人类胎盘对 ART 和/或不孕引起的表观遗传缺陷很敏感,我们强调要考虑到性别和父亲因素的重要性,并且并非所有的 ART 胚胎都易感。