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Recent admixture in an Indian population of African ancestry.

ABSTRACT: Identification and study of genetic variation in recently admixed populations not only provides insight into historical population events but also is a powerful approach for mapping disease loci. We studied a population (OG-W-IP) that is of African-Indian origin and has resided in the western part of India for 500 years; members of this population are believed to be descendants of the Bantu-speaking population of Africa. We have carried out this study by using a set of 18,534 autosomal markers common between Indian, CEPH-HGDP, and HapMap populations. Principal-components analysis clearly revealed that the African-Indian population derives its ancestry from Bantu-speaking west-African as well as Indo-European-speaking north and northwest Indian population(s). STRUCTURE and ADMIXTURE analyses show that, overall, the OG-W-IPs derive 58.7% of their genomic ancestry from their African past and have very little inter-individual ancestry variation (8.4%). The extent of linkage disequilibrium also reveals that the admixture event has been recent. Functional annotation of genes encompassing the ancestry-informative markers that are closer in allele frequency to the Indian ancestral population revealed significant enrichment of biological processes, such as ion-channel activity, and cadherins. We briefly examine the implications of determining the genetic diversity of this population, which could provide opportunities for studies involving admixture mapping.

SUBMITTER: Narang A

PROVIDER: S-EPMC3135806 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature

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Recent admixture in an Indian population of African ancestry.

Narang Ankita A Jha Pankaj P Rawat Vimal V Mukhopadhyay Arijit A Dash Debasis D Basu Analabha A Mukerji Mitali M

American journal of human genetics 20110707 1

Identification and study of genetic variation in recently admixed populations not only provides insight into historical population events but also is a powerful approach for mapping disease loci. We studied a population (OG-W-IP) that is of African-Indian origin and has resided in the western part of India for 500 years; members of this population are believed to be descendants of the Bantu-speaking population of Africa. We have carried out this study by using a set of 18,534 autosomal markers c ...[more]

PMID: 21737057

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Recent admixture in an Indian population of African ancestry.

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Recent admixture in an Indian population of African ancestry.

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