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Genome-wide scan of 29,141 African Americans finds no evidence of directional selection since admixture.

ABSTRACT: The extent of recent selection in admixed populations is currently an unresolved question. We scanned the genomes of 29,141 African Americans and failed to find any genome-wide-significant deviations in local ancestry, indicating no evidence of selection influencing ancestry after admixture. A recent analysis of data from 1,890 African Americans reported that there was evidence of selection in African Americans after their ancestors left Africa, both before and after admixture. Selection after admixture was reported on the basis of deviations in local ancestry, and selection before admixture was reported on the basis of allele-frequency differences between African Americans and African populations. The local-ancestry deviations reported by the previous study did not replicate in our very large sample, and we show that such deviations were expected purely by chance, given the number of hypotheses tested. We further show that the previous study's conclusion of selection in African Americans before admixture is also subject to doubt. This is because the FST statistics they used were inflated and because true signals of unusual allele-frequency differences between African Americans and African populations would be best explained by selection that occurred in Africa prior to migration to the Americas.

SUBMITTER: Bhatia G

PROVIDER: S-EPMC4185117 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Genome-wide scan of 29,141 African Americans finds no evidence of directional selection since admixture.

Bhatia Gaurav G Tandon Arti A Patterson Nick N Aldrich Melinda C MC Ambrosone Christine B CB Amos Christopher C Bandera Elisa V EV Berndt Sonja I SI Bernstein Leslie L Blot William J WJ Bock Cathryn H CH Caporaso Neil N Casey Graham G Deming Sandra L SL Diver W Ryan WR Gapstur Susan M SM Gillanders Elizabeth M EM Harris Curtis C CC Henderson Brian E BE Ingles Sue A SA Isaacs William W De Jager Phillip L PL John Esther M EM Kittles Rick A RA Larkin Emma E McNeill Lorna H LH Millikan Robert C RC Murphy Adam A Neslund-Dudas Christine C Nyante Sarah S Press Michael F MF Rodriguez-Gil Jorge L JL Rybicki Benjamin A BA Schwartz Ann G AG Signorello Lisa B LB Spitz Margaret M Strom Sara S SS Tucker Margaret A MA Wiencke John K JK Witte John S JS Wu Xifeng X Yamamura Yuko Y Zanetti Krista A KA Zheng Wei W Ziegler Regina G RG Chanock Stephen J SJ Haiman Christopher A CA Reich David D Price Alkes L AL

American journal of human genetics 20140918 4

The extent of recent selection in admixed populations is currently an unresolved question. We scanned the genomes of 29,141 African Americans and failed to find any genome-wide-significant deviations in local ancestry, indicating no evidence of selection influencing ancestry after admixture. A recent analysis of data from 1,890 African Americans reported that there was evidence of selection in African Americans after their ancestors left Africa, both before and after admixture. Selection after a ...[more]

PMID: 25242497

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Dataset Information

Genome-wide scan of 29,141 African Americans finds no evidence of directional selection since admixture.

Publications

Genome-wide scan of 29,141 African Americans finds no evidence of directional selection since admixture.

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