PT  - JOURNAL ARTICLE
AU  - Soheil Baharian
AU  - Maxime Barakatt
AU  - Christopher R. Gignoux
AU  - Suyash Shringarpure
AU  - Jacob Errington
AU  - William J. Blot
AU  - Carlos D. Bustamante
AU  - Eimear E. Kenny
AU  - Scott M. Williams
AU  - Melinda C. Aldrich
AU  - Simon Gravel
TI  - The Great Migration and African-American genomic diversity
AID  - 10.1101/029173
DP  - 2015 Jan 01
TA  - bioRxiv
PG  - 029173
4099  - http://biorxiv.org/content/early/2015/10/15/029173.short
4100  - http://biorxiv.org/content/early/2015/10/15/029173.full
AB  - Genetic studies of African-Americans identify functional variants, elucidate historical and genealogical mysteries, and reveal basic biology. However, African-Americans have been under-represented in genetic studies, and little is known about nation-wide patterns of genomic diversity in the population. Here, we present a comprehensive assessment of African-American genomic diversity using genotype data from nationally and regionally representative cohorts. We find higher African ancestry in southern United States compared to the North and West. We show that relatedness patterns track north- and west-bound routes followed during the Great Migration, suggesting that admixture occurred predominantly in the South prior to the Civil War and that ancestry-biased migration is responsible for regional differences in ancestry. Rare genetic traits among African-Americans can therefore be shared over long geographic distances along the Great Migration routes, yet their distribution over short distances remains highly structured. This study clarifies the role of recent demography in shaping African-American genomic diversity.