没有证据表明在自然生育人口中基于HLA基因型的分类交配
Gillian L Meeks1,2, Brooke Scelza3,2, Katherine M Kichula4
1Graduate Program in Integrative Genetics and Genomics, University of California Davis, Davis, CA, USA.
bioRxiv : the preprint server for biology
|July 14, 2025
概括
希姆巴人群中的伴侣选择不显示对人类白细胞抗原 (HLA) 不相似性的偏好. 这表明HLA多样性,而不是不分类的交配,可能驱动免疫基因进化.
科学领域:
- 人类进化遗传学 人类进化遗传学
- 免疫遗传学 免疫遗传学
- 人口遗传学 人口遗传学
背景情况:
- 基于人类白细胞抗原 (HLA) 基因的分类交配的证据在不同种群中不一致.
- 之前对HLA- تتزاوج的研究已经产生了混合的结果,有些人建议在国际人口中进行各种交配.
- 很少有研究检查了小规模的基于HLA的伴侣选择,与人类进化历史相关的内合性群体.
研究的目的:
- 调查HLA不相似性是否影响纳米比亚内婚族群Himba的伴侣选择.
- 为了比较HLA遗传资料在选择 (爱情/非正式) 与安排的伙伴关系.
- 评估与基于HLA的病原体结合相关的后代基因型的潜在健康益处.
主要方法:
- 在366个个体中对八个经典的HLA基因进行了有针对性的测序.
- 记录自我报告的伙伴关系类型和非正式伙伴关系.
- 在249个已知的伴侣关系 (选择与安排) 中分析HLA不相似性.
- 对潜在后代的基于HLA的病原体结合亲缘关系的评估.
主要成果:
- 在选择和安排的伙伴关系之间没有发现HLA不相似性的显著差异.
- 伙伴关系类型与HLA不相似性的随机分布没有区别.
- 在安排和选择的合作伙伴之间没有观察到基于HLA的病原体结合亲缘关系的差异.
- 在HLA区域中广泛的单 haplotype共享表明最近的积极选择.
结论:
- 希姆巴人之间的伴侣选择似乎不是由最大限度地提高HLA差异驱动的.
- 洪巴人的高背景HLA多样性可能会限制不合类配对的健康益处.
- 波动的阳性选择在维持HLA多态性方面可能比不分类的交配发挥更重要的作用.
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