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人类突变的热点指向了精子中的克隆扩张
Vladimir Seplyarskiy1,2, Mikhail A Moldovan1, Evan Koch1
1Department of Biomedical Informatics, Harvard Medical School, Boston, MA, USA.
medRxiv : the preprint server for health sciences
|June 30, 2025
概括
精子 (CES) 中的克隆扩张增加了传给后代的基因突变率. 这项研究确定了40个候选CES驱动基因,影响遗传疾病流行率和疾病关联研究.
科学领域:
- 遗传学 是一个遗传学.
- 进化生物学 进化生物学
- 人类繁殖人类的繁殖.
背景情况:
- 赋予选择性优势的突变可以在更新组织中引起克隆扩张.
- 与体内组织不同,驱动精子细胞 (CES) 克隆扩张的突变是可遗传的,这增加了CES驱动者的有效de novo突变率.
- 最初通过导致阿珀特综合征的反复出现的新突变来确定CES.
研究的目的:
- 开发一种系统的方法来识别CES驱动器作为人类新突变的热点.
- 研究CES对突变率和遗传疾病患病率的影响.
主要方法:
- 分析了54,715个罕见疾病三组,6,065个对照三组和807,162个个体的种群变异数据.
- 鉴定具有新突变率的基因与疾病确定模型不一致.
- 根据突变类型 (功能损失与功能增益) 对候选CES驱动者的分类.
主要成果:
- 鉴定了23个具有超变性功能丧失 (LoF) 位点的候选CES驱动基因.
- 鉴定了17个具有超可变误解突变的候选CES驱动基因,表明功能的获取 (GoF).
- 在精子中,CES增加了LoF基因的平均突变率约17倍,而在精子中的GoF位点则增加了500倍.
结论:
- CES显著提高了男性生殖系的突变率,增加了遗传疾病的患病率.
- 在人类群体中,CES可以掩盖负面选择的影响.
- CES可能导致错误的阳性疾病关联,因为19个LoF CES候选驾驶员中只有9个显示出明显的疾病因果关系.
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