AncestryDNA, San Francisco, California 94107, USA.
AncestryDNA, Lehi, Utah 84043, USA.
Nat Commun. 2017 Feb 7;8:14238. doi: 10.1038/ncomms14238.
Despite strides in characterizing human history from genetic polymorphism data, progress in identifying genetic signatures of recent demography has been limited. Here we identify very recent fine-scale population structure in North America from a network of over 500 million genetic (identity-by-descent, IBD) connections among 770,000 genotyped individuals of US origin. We detect densely connected clusters within the network and annotate these clusters using a database of over 20 million genealogical records. Recent population patterns captured by IBD clustering include immigrants such as Scandinavians and French Canadians; groups with continental admixture such as Puerto Ricans; settlers such as the Amish and Appalachians who experienced geographic or cultural isolation; and broad historical trends, including reduced north-south gene flow. Our results yield a detailed historical portrait of North America after European settlement and support substantial genetic heterogeneity in the United States beyond that uncovered by previous studies.
尽管在从遗传多态性数据描绘人类历史方面取得了进展，但在确定最近人口统计学的遗传特征方面的进展有限。在这里，我们从美国起源的 77 万多名个体的超过 5 亿个遗传（亲缘关系，IBD）连接网络中识别出北美的近期精细人口结构。我们检测到网络中的密集连接集群，并使用超过 2000 万条谱系记录数据库对这些集群进行注释。IBD 聚类捕捉到的近期人口模式包括移民，如斯堪的纳维亚人和法裔加拿大人；具有大陆混合血统的群体，如波多黎各人；经历地理或文化隔离的定居者，如阿米什人和阿巴拉契亚人；以及包括南北基因流减少在内的广泛历史趋势。我们的研究结果描绘了欧洲人定居后的北美的详细历史画卷，并支持美国存在比以往研究揭示的更大的遗传异质性。
