南亚种群的内生和有害变异
Jeffrey D Wall1, Murillo F Rodrigues2
1Division of Genetics, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, 97006, USA. walljef@ohsu.edu.
Scientific reports
|October 6, 2025
概括
血缘关系或近亲繁殖会增加死亡率和疾病风险,特别是在南亚. 这项研究量化了各种种群中的内生繁殖水平和遗传成本,揭示了孤立群体中更高的突变负担.
科学领域:
- 遗传学 是一个遗传学.
- 人口遗传学 人口遗传学
- 人类进化人类进化
背景情况:
- 血缘关系,即相关个体的后代,与增加的死亡率和疾病有关.
- 超过10亿人居住在血缘关系婚姻普遍存在的地区,这与罕见衰退性疾病的高发病率有关.
- 目前用于估计近亲繁殖的方法存在局限性.
研究的目的:
- 估计不同种群,主要来自南亚的内生繁殖程度.
- 发现当前近亲繁殖估计技术的缺陷.
- 通过分析有害突变来量化近亲繁殖的遗传成本.
主要方法:
- 分析不同种族和民族群体的血缘关系比例,重点关注南亚.
- 不同国家和子组之间的内生繁殖水平的比较.
- 识别具有减少有效种群规模的孤立种群.
- 在同卵性性 (ROH) 个体中对有害突变的量化.
主要成果:
- 血缘关系的比例有很大差异,从孟加拉国的9.3%到巴基斯坦的42.8% (医疗队伍) 和印度阿迪瓦西群体的0-100%.
- 印度的子组表现出比其他地方的同行更高的血缘关系.
- 孤立的种群显示出内生繁殖的增加和有效种群大小的减少.
- 长ROH中有害突变密度更高,支持净化选择模型.
- 在小,孤立的种群中观察到净化选择的效率降低.
结论:
- 亲生繁殖是影响全球各种人口的健康和遗传多样性的重要因素,特别是在南亚.
- 这项研究提供了对近亲繁殖及其遗传后果的精细估计.
- 研究结果强调了人口规模和隔离对遗传健康和进化过程的影响.
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