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人类胚胎在早期发育过程中具有复杂的马赛克主义,在早期发育过程中广泛存在形细胞
Fan Zhai1,2,3,4,5, Siming Kong1,2,3,4,5,6, Shi Song1,2,3,4,5
1Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China.
Cell discovery
|September 23, 2024
概括
人类胚胎经常表现出遗传马赛克主义,这挑战了当前的前植入前遗传测试 (PGT-A) 实践. 这项研究揭示了广泛的染色体异常,这表明PGT-A可能会误解可行的胚胎.
科学领域:
- 生殖生物学 生殖生物学
- 人类遗传学 人类遗传学
- 发育生物学是发展生物学.
背景情况:
- 在辅助生殖技术中,广泛使用的是前植入基因测试 (PGT-A).
- 目前的PGT-A协议依赖于关于胚胎遗传学的假设,这些假设可能无法完全验证.
- 人们担心PGT-A可能会导致丢弃具有可行的发育潜力的胚胎.
研究的目的:
- 研究人类胚胎中遗传马赛克的流行和性质.
- 评估当前PGT-A指南的准确性和影响.
- 了解人类早期发展的遗传景观.
主要方法:
- 单细胞全基因组测序来自20个体外培养的人类胚胎细胞的1133个细胞.
- 从早期人类胚胎 (体外培养,第8-14天) 和胚胎/胎儿器官中分析了20945个单细胞.
- 在单个细胞中描述形状的速率和模式.
主要成果:
- 所有20个分析的胚芽细胞都表现出马赛克主义,由于线粒错误,每个胚胎约有25%的形细胞.
- 70%的芽细胞囊中含有"染色体补充"细胞,这表明标准PGT-A.中对马赛克的低估.
- 在所有分析的胚胎和胎儿组织中,有97% (20,945个细胞) 是马赛克细胞,大多数形细胞具有最小的染色体错误 (≤2).
结论:
- 人类胚胎表现出高频率的遗传马赛克主义,其特征是由由线粒错误引起的无倍体细胞.
- 目前的PGT-A实践可能受到胚胎遗传学的不完全理解的限制,可能导致误诊.
- 需要进一步的研究来完善PGT-A方法,以便在广泛的马赛克主义背景下准确评估胚胎生存能力.
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