Epimutations in Offspring Produced by Assisted Reproductive Technologies (ART)

描述（由申请人提供）：本项目旨在获得第一次全面评估的表观遗传缺陷（表观突变）诱导使用辅助生殖技术（ART）在后代生产。将使用尖端、高通量表观基因组和基因组技术，在通过卵胞浆内单精子注射（ICSI）产生的小鼠中评估DNA甲基化模式和基因表达模式异常的全基因组发生率。此外，将通过确定ART产生的小鼠中出现表位突变的精确时间，以及通过辨别ART过程的三个特定方面-促性腺激素刺激卵泡生成、植入前胚胎的长期培养和胚胎移植-对表位突变诱导的相对贡献，研究ART诱导的表位突变的病因。最后，将检查ART诱导的表观突变的命运，以确定这些表观突变是否在胚胎发生或配子发生期间通过表观遗传重编程得到一致校正。本申请中提出的研究的意义在于，它将包括高（单碱基）分辨率， ART对全基因组表观遗传编程的破坏性影响的全面分析，并且它将促进ART诱导的表观突变的起源、病因、程度和fte的受控的、前瞻性的研究，包括ART过程的多个不同方面对所产生的后代中表观突变的诱导的相对贡献的平行的、同时的研究。拟议的研究是创新和及时的，因为我们现在能够生成前所未有的规模和分辨率的数据集，描述ART后代中异常的表观遗传编程和基因表达，我们可以用这些来了解ART诱导的表观突变的起源，后果和命运，对基础生物学和人类健康具有重大意义。由此产生的ART诱导的表观突变的病因学的增强的理解将告知临床ART方案的未来修改，以最大限度地减少ART衍生的人类后代中的表观突变的诱导，从而减少由该技术产生的个体中表观遗传疾病的发生。

DESCRIPTION (provided by applicant): This project is designed to obtain the first comprehensive assessment of epigenetic defects (epimutations) induced by the use of assisted reproductive technologies (ART) in the offspring produced. The genome-wide occurrence of abnormalities in DNA methylation patterns and gene expression patterns will be assessed in mice produced by intracytoplasmic sperm injection (ICSI) using cutting-edge, high-throughput epigenomic and genomic technologies. In addition, the etiology of ART-induced epimutations will be investigated by determining the precise timing of appearance of epimutations in mice produced by ART, as well as by discerning the relative contribution of each of three specific aspects of the ART process - gonadotropin stimulation of folliculogenesis, prolonged culture of preimplantation embryos, and embryo transfer - to the induction of epimutations. Finally, the fate of ART-induced epimutations will be examined to determine if these are consistently corrected by epigenetic reprogramming during either embryogenesis or gametogenesis. The significance of the research proposed in this application is that it will include high (single-base) resolution, comprehensive analyses of the disruptive effects of ART on epigenetic programming genome-wide, and it will facilitate controlled, prospective studies of the genesis, etiology, extent and fte of epimutations induced by ART, including parallel, simultaneous studies of the relative contribution(s) of multiple different aspects of the ART process to the induction of epimutations in the offspring produced. The proposed research is innovative and timely because we are now able to generate datasets of unprecedented scale and resolution describing abnormal epigenetic programming and gene expression in ART offspring, and we can use these to understand the genesis, consequences and fate of ART-induced epimutations in ways that will have significant implications for basic biology and human health. The resulting enhanced understanding of the etiology of ART-induced epimutations will inform future modifications of clinical ART protocols to minimize the induction of epimutations in ART-derived human offspring and thereby reduce the occurrence of epigenetic disorders in individuals produced by this technology.