Contrasting X-Linked and Autosomal Diversity across 14 Human Populations
Contrasting X-Linked and Autosomal Diversity across 14 Human Populations
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DOI：
10.1016/j.ajhg.2014.04.011
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发表时间：
2014-06-05
影响因子：
9.8
通讯作者：
Keinan, Alon
中科院分区：
文献类型：
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作者：
Arbiza, Leonardo;Gottipati, Srikanth;Keinan, Alon
对比人类X染色体(X)和常染色体的遗传多样性有助于理解男性和女性之间的历史差异以及自然选择的影响。之前基于较小数据集的研究留下了一些问题，即经验模式如何延伸到更多的人群，以及哪些力量可以解释它们。在这里，我们通过分析来自14个群体的569名女性的完整基因组的X/A核苷酸多样性比率来解决这些问题。结果表明，每个大陆种群的X/A多样性相似，但欧洲(EUR)和东亚(ASN)种群的X/A多样性明显低于非洲(AFR)种群。所有群体的X/A多样性都随着与基因距离的增加而增加，这突出了减少多样性的选择对X的影响比对常染色体的影响更大。然而，相对X/A差异(之间)。两个种群)与基因的距离是不变的，这表明选择并不会导致非非洲人X/A多样性的相对减少(欧盟与非洲之比为0.842+/-0.012，非洲人与非洲之比为0.820+/-0.032)。最后，根据人类人口历史的最新研究，一系列具有不同人口瓶颈、扩张和迁移的模型约占观察到的相对X/A多样性从预期值1下降的一半。它们预测欧盟与AFR的比较值在0.91至0.94之间，ASN与AFR的比较值在0.91至0.92之间。可以通过更极端的人口事件预测进一步的减少，而不是。最新的研究，但在没有这些的情况下，也受到历史上性别偏见的人口事件或其他过程的影响。
Contrasting the genetic diversity of the human X chromosome (X) and autosomes has facilitated understanding historical differences between males and females and the influence of natural selection. Previous studies based on smaller data sets have left questions regarding how empirical patterns extend to additional populations and which forces can explain them. Here, we address these questions by analyzing the ratio of X-to-autosomal (X/A) nucleotide diversity with the complete genomes of 569 females from 14 populations. Results show that X/A diversity is similar within each continental group but notably lower in European (EUR) and East Asian (ASN) populations than in African (AFR) populations. X/A diversity increases in all populations with increasing distance from genes, highlighting the stronger impact of diversity-reducing selection on X than on the autosomes. However, relative X/A diversity (between. two populations) is invariant with distance from genes, suggesting that selection does not drive the relative reduction in X/A diversity in non-Africans (0.842 +/- 0.012 for EUR-to-AFR and 0.820 +/- 0.032 for ASN-to-AFR comparisons). Finally, an array of models with varying population bottlenecks, expansions, and migration from the latest studies of human demographic history account for about half of the observed reduction in relative X/A diversity from the expected value of 1. They predict values between 0.91 and 0.94 for EUR-to-AFR comparisons and between 0.91 and 0.92 for ASN-to-AFR comparisons. Further reductions can be predicted by more extreme demographic events in excess of those captured by. the latest studies but, in the absence of these, also by historical sex-biased demographic events or other processes.