母亲年龄和整个基因组中介性重组的失败与人类的三重化概念有关
Ludovica Picchetta1, Christian Simon Ottolini2, Xin Tao3
1Juno Genetics, Reproductive Genetics, Rome, Italy; University of Teramo, Department of Department of Bioscience and Agro-Food and Environmental Technology, Teramo, Italy.
American journal of human genetics
|October 15, 2025
概括
三倍体和双倍体受孕,是导致流产的常见原因,与母亲的年龄和潜在的个人风险因素有关. 这项研究揭示了对变和卵细胞形成的见解,影响了人类生殖生物学.
科学领域:
- 生殖生物学 生殖生物学
- 人类遗传学 人类遗传学
- 发展生物学 发展生物学
背景情况:
- 三倍体和二倍体受孕是不可行的,导致10%的人类怀孕损失.
- 这些染色体异常的确切原因,特别是在受孕时,仍然不完全理解.
研究的目的:
- 研究人类胚胎中三倍体和单倍体的发病率和病因因素.
- 为了探索母亲的年龄,个人风险,和发生的体积之间的关系.
主要方法:
- 对大量数据集 (96,660例活检) 和从细胞内精子注射 (ICSI) 获得的人类母细胞胚胎的验证集 (44,324) 的分析.
- 三重胚胎活检和父母DNA的基因型分析.
- 统计分析以确定风险因素和影响.
主要成果:
- 分析的人类受孕的1.1%显示出额外或缺失的染色体组.
- 在增加母亲年龄和增加三倍性/性风险 (每年增加1046倍的风险) 之间发现了显著的关联.
- 个人风险影响的证据在0.03%的夫妇中观察到,他们有三个或更多受影响的胚胎. 孕产妇的三倍体受孕起源于半变异I (1/3) 和半变异II (2/3).
- 在0.05%的胚胎中确定了全基因组的母性异倍体. 七个胚胎表现出完全失败的介质重组.
结论:
- 母亲年龄是ICSI衍生的胚胎中三倍性/两倍性发育的重要风险因素.
- 这些发现表明潜在的个人风险效应,并为人类卵细胞形成和介质性错误提供了新的见解,包括普遍的重组失败.
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