非常异质合体的amphioxus基因组的生殖线de novo突变率
Jing Xue1,2,3, Lei Tao1, Junwei Cao4
1State Key Laboratory of Biocontrol, School of Life Sciences, Guangdong Provincial Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University, Guangzhou, Guangdong, China.
Molecular biology and evolution
|January 14, 2026
概括
两动物的新生菌系突变 (DNM) 显示出与脊椎动物相似的突变率. 高异构性主要是由于有效种群规模较大,而不是突变率增加.
科学领域:
- 进化遗传学的进化遗传学
- 基因组学就是基因组学.
- 分子进化的分子进化.
背景情况:
- 生殖系新生突变 (DNM) 对于遗传变异至关重要.
- 了解高度异合体基因组的突变模式,如安菲奥克斯,是具有挑战性的.
- 阿姆菲奥克斯表现出异常高的基因组异构性 (3.24.2%).
研究的目的:
- 为了研究高度异构的amphioxus基因组中的生殖线新突变 (DNM) 的模式和速率.
- 为了确定两动物中高异构性驱动因素:有效种群规模或突变率.
- 建立一个可通用的策略来研究异合体基因组中的DNM.
主要方法:
- 深度短读全基因组测序的两个世代的两 (Branchiostoma floridae) 血统 (2 个父母,104 个后代).
- 为准确的DNM识别开发一个代基意识的父组合框架.
- 计算全基因组突变率和有效种群大小.
主要成果:
- 检测到242个高可信度DNM,产生一个全基因组突变率为5.89 × 10−9每基每代,与脊椎动物相比.
- 估计有效人口大小约为170万,表明大人口大小驱动异卵性.
- 在DNM中没有观察到整体的性别偏差,但在早期突变和后阴性突变中存在父性偏差;由于低甲基化,CpG>TpG DNM较低.
结论:
- 安菲奥克苏斯的突变率与脊椎动物相似,因有效种群规模较大而具有较高的异构性.
- 不同的突变动态,包括父系起源偏差和减少的CpG>TpG突变,存在于amphioxus.
- 这项研究提供了第一个DNM测量安菲奥克苏斯和研究突变在异质合体基因组的新策略.
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