在沙特阿拉伯人口中人口结构和遗传变异的模式
D K Malomane1, M P Williams2, C D Huber2
1Center for Genetic Epidemiology, Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA.
bioRxiv : the preprint server for biology
|January 27, 2025
概括
沙特阿拉伯的人口历史和文化实践,如内婚关系,显著影响了遗传变异. 这项研究揭示了丰富的有害等位基因,影响了人口健康,并强调了对多样化基因组数据的需求.
科学领域:
- 人口遗传学 人口遗传学
- 人类进化研究 人类进化研究
- 基因组学就是基因组学.
背景情况:
- 阿拉伯半岛是早期人类从非洲迁徙的关键地区.
- 现代沙特阿拉伯人是古代人口的后裔,他们在移民分裂后留下来.
- 文化习惯,如内婚,可能会影响沙特阿拉伯人内的遗传多样性.
研究的目的:
- 调查人口历史和文化习惯如何塑造沙特阿拉伯的遗传变异.
- 在沙特人口中识别遗传子集群及其祖先组成部分.
- 分析有害等位基因的负担及其与人口历史和近亲繁殖的关系.
主要方法:
- 基因定型了3,352个个体,以根据地理和部落分布确定基因子集群.
- 利用302个个体的全基因组测序 (WGS) 数据分析了25488981个遗传变异.
- 与全球人口 (例如,gnomAD) 进行沙特遗传变异的比较,包括有害的等位基因,并分析了同性.
主要成果:
- 在沙特阿拉伯人中确定了12个遗传子集群,与地理和祖先相关.
- 与非洲人/非裔美国人相比,沙特人口的有害等位基因比例更高.
- 具有较高内生繁殖和较小有效种群规模的子群体显示出有害等位基因的丰富性更大.
结论:
- 沙特阿拉伯的人口历史和内婚关系显著影响了遗传变异模式.
- 观察到的有害等位基因的丰富对人口健康有潜在的影响.
- 强调需要对多样化的种群进行测序,以准确地解释医学和药物基因组发现.
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