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Clustering of 770,000 genomes reveals post-colonial population structure of North America.

ABSTRACT: 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.

SUBMITTER: Han E

PROVIDER: S-EPMC5309710 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Clustering of 770,000 genomes reveals post-colonial population structure of North America.

Han Eunjung E Carbonetto Peter P Curtis Ross E RE Wang Yong Y Granka Julie M JM Byrnes Jake J Noto Keith K Kermany Amir R AR Myres Natalie M NM Barber Mathew J MJ Rand Kristin A KA Song Shiya S Roman Theodore T Battat Erin E Elyashiv Eyal E Guturu Harendra H Hong Eurie L EL Chahine Kenneth G KG Ball Catherine A CA

Nature communications 20170207

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 genealog ...[more]

PMID: 28169989

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Clustering of 770,000 genomes reveals post-colonial population structure of North America.

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Clustering of 770,000 genomes reveals post-colonial population structure of North America.

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