由TOP6BL变种引起的非阻塞性亚子精的机制
Chao Wang1,2,3, Yanwei Sha4, Yayun Ji3
1Department of Andrology and Sexual Medicine, First Affiliated Hospital of Fujian Medical University, Fuzhou, China.
概括
TOP6BL基因中的遗传变异与非阻塞性精子缺血症 (NOA) 相关,这是男性不孕症的原因. 这些TOP6BL变种破坏了DNA双链断裂的形成,导致介质性停止和精子生成受损.
科学领域:
- 遗传学 遗传学 是一个
- 生殖生物学 生殖生物学
- 分子生物学分子生物学
背景情况:
- 非阻塞性精症 (NOA) 影响大约1%的男性,是男性不孕症的重要原因,许多病例的遗传起源不明.
- TOP6BL基因在精子生成中的作用及其与NOA的关联在很大程度上仍未被探索,特别是在多样化的群体中.
研究的目的:
- 为了研究在汉族中国血缘亲属家庭中NOA的遗传基础.
- 确定与NOA相关的TOP6BL基因中的特定变异,并阐明它们对男性生育能力的功能影响.
主要方法:
- 整体外体序列测序用于识别受影响家庭中的遗传变异.
- 进行了功能分析,包括蛋白质相互作用测定和使用小鼠模型的体内研究,以评估已识别的TOP6BL变体的影响.
- 在受影响的个体和模型生物体中分析了 meiotic DNA 双链断裂 (DSB) 形成和精子生成进展.
主要成果:
- 两种新的TOP6BL变异,c.1067C>G:p.Pro356Arg和c.1543C>T:p.Arg515Ter,被确定并与研究家庭中的NOA相关.
- 这些变异被发现会破坏中介性DNA的DSB形成,导致在精子生成的zygotene阶段中介性停止.
- 功能性研究表明,p.Arg515Ter变体损害了REC114结合和SPO11相互作用,而p.Pro356Arg影响了TOP6BL自二分化,这两种影响男性生育能力.
结论:
- TOP6BL变种是NOA的重要原因,通过破坏基本的介质过程,如DNADSB形成来起作用.
- 这些发现强调了TOP6BL基因,特别是其中间区域在成功的精子生成和男性生育能力中的关键作用.
- 了解这些遗传机制为男性不孕症和潜在的诊断目标提供了新的见解.
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