胎盘介于胎儿与母体之间,是维持胎儿宫内生长发育的重要器官。在胎盘的正常发育过程中,子宫正常蜕膜化、滋养层细胞粘附与侵袭、胎盘血管生成与形成、胎盘印记基因表达都受到表观遗传修饰(如DNA甲基化、组蛋白修饰、非编码RNA等)的调控。研究已经证实环境因素如重金属、化合物、现代辅助生殖技术、营养物质均可导致胎盘上多种基因的表观遗传修饰异常。此外,胎盘基因表达存在性别差异也可能与表观遗传修饰有关。目前,在临床上可运用产前DNA甲基化水平分析技术检测异常的表观遗传修饰,并在疾病早期发现并做出诊断,从而为疾病预防及治疗提供依据。本文对胎盘正常发育过程中表观遗传修饰的调控及环境因素所致的胎盘基因表观遗传改变进行了综述,以期对胎盘相关疾病的诊断与治疗提供借鉴和参考。

The placenta is vital to fetal growth and development, as it bridges the fetus and the mother. Genome-wide epigenetic regulations (e.g., DNA methylation, histone modifications, non-coding RNAs) participate in many aspects of placenta development, including decidua of the uterus, trophoblast cell adhesion and invasion, angiogenesis and placental imprinted gene expression. Environmental factors during pregnancy, such as heavy metals, chemical compounds, modern assisted reproductive technology and the nutrient conditions, may cause abnormal placental epigenetics. Furthermore, sex differential expression of placental genes also contributes to epigenetic modifications. As prenatal DNA methylation analysis can detect abnormal epigenetic modifications, it is a potential diagnosis tool for early stage diseases and may help disease intervention and treatment. Here, we review not only regulations of epigenetic modifications during development of the placenta, but also the influences of environmental factors. The potential value for diagnosis and treatment is also discussed.