Dataset Information

Ethiopian genetic diversity reveals linguistic stratification and complex influences on the Ethiopian gene pool.

ABSTRACT: Humans and their ancestors have traversed the Ethiopian landscape for millions of years, and present-day Ethiopians show great cultural, linguistic, and historical diversity, which makes them essential for understanding African variability and human origins. We genotyped 235 individuals from ten Ethiopian and two neighboring (South Sudanese and Somali) populations on an Illumina Omni 1M chip. Genotypes were compared with published data from several African and non-African populations. Principal-component and STRUCTURE-like analyses confirmed substantial genetic diversity both within and between populations, and revealed a match between genetic data and linguistic affiliation. Using comparisons with African and non-African reference samples in 40-SNP genomic windows, we identified "African" and "non-African" haplotypic components for each Ethiopian individual. The non-African component, which includes the SLC24A5 allele associated with light skin pigmentation in Europeans, may represent gene flow into Africa, which we estimate to have occurred ~3 thousand years ago (kya). The non-African component was found to be more similar to populations inhabiting the Levant rather than the Arabian Peninsula, but the principal route for the expansion out of Africa ~60 kya remains unresolved. Linkage-disequilibrium decay with genomic distance was less rapid in both the whole genome and the African component than in southern African samples, suggesting a less ancient history for Ethiopian populations.

SUBMITTER: Pagani L

PROVIDER: S-EPMC3397267 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Ethiopian genetic diversity reveals linguistic stratification and complex influences on the Ethiopian gene pool.

Pagani Luca L Kivisild Toomas T Tarekegn Ayele A Ekong Rosemary R Plaster Chris C Gallego Romero Irene I Ayub Qasim Q Mehdi S Qasim SQ Thomas Mark G MG Luiselli Donata D Bekele Endashaw E Bradman Neil N Balding David J DJ Tyler-Smith Chris C

American journal of human genetics 20120621 1

Humans and their ancestors have traversed the Ethiopian landscape for millions of years, and present-day Ethiopians show great cultural, linguistic, and historical diversity, which makes them essential for understanding African variability and human origins. We genotyped 235 individuals from ten Ethiopian and two neighboring (South Sudanese and Somali) populations on an Illumina Omni 1M chip. Genotypes were compared with published data from several African and non-African populations. Principal- ...[more]

PMID: 22726845

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Dataset Information

Ethiopian genetic diversity reveals linguistic stratification and complex influences on the Ethiopian gene pool.

Publications

Ethiopian genetic diversity reveals linguistic stratification and complex influences on the Ethiopian gene pool.

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