Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton CB10 1SA, UK; Department of Forensic Science and Criminology, Dubai Police GHQ, Dubai, United Arab Emirates.
Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham B15 2TT, UK; Centre for Computational Biology, University of Birmingham, Birmingham B15 2TT, UK.
Cell. 2021 Sep 2;184(18):4612-4625.e14. doi: 10.1016/j.cell.2021.07.013. Epub 2021 Aug 4.
The Middle East region is important to understand human evolution and migrations but is underrepresented in genomic studies. Here, we generated 137 high-coverage physically phased genome sequences from eight Middle Eastern populations using linked-read sequencing. We found no genetic traces of early expansions out-of-Africa in present-day populations but found Arabians have elevated Basal Eurasian ancestry that dilutes their Neanderthal ancestry. Population sizes within the region started diverging 15-20 kya, when Levantines expanded while Arabians maintained smaller populations that derived ancestry from local hunter-gatherers. Arabians suffered a population bottleneck around the aridification of Arabia 6 kya, while Levantines had a distinct bottleneck overlapping the 4.2 kya aridification event. We found an association between movement and admixture of populations in the region and the spread of Semitic languages. Finally, we identify variants that show evidence of selection, including polygenic selection. Our results provide detailed insights into the genomic and selective histories of the Middle East.
中东地区对于理解人类进化和迁徙非常重要，但在基因组研究中代表性不足。在这里，我们使用链接读取测序技术，从八个中东人群中生成了 137 个高覆盖率的物理相位基因组序列。我们没有发现当今人群中早期非洲扩张的遗传痕迹，但发现阿拉伯人具有升高的基底欧亚大陆祖先，这降低了他们的尼安德特人祖先。该地区内的人口规模在 15-20 千年前开始分化，当时黎凡特人扩张，而阿拉伯人维持着较小的人口规模，其祖先来自当地的狩猎采集者。大约在 6 千年前阿拉伯地区干旱化时，阿拉伯人经历了一次人口瓶颈，而黎凡特人在 4.2 千年前的干旱化事件中经历了一个独特的瓶颈。我们发现该地区人口迁移和混合与闪米特语的传播之间存在关联。最后，我们鉴定了一些显示选择证据的变体，包括多基因选择。我们的研究结果为中东的基因组和选择性历史提供了详细的见解。
