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Evidence from Cameroon reveals differences in the genetic structure and histories of chimpanzee populations.

ABSTRACT: The history of the genus Pan is a topic of enduring interest. Chimpanzees (Pan troglodytes) are often divided into subspecies, but the population structure and genetic history of chimpanzees across Africa remain unclear. Some population genetics studies have led to speculation that, until recently, this species constituted a single population with ongoing gene flow across its range, which resulted in a continuous gradient of allele frequencies. Chimpanzees, designated here as P. t. ellioti, occupy the Gulf of Guinea region that spans southern Nigeria and western Cameroon at the center of the distribution of this species. Remarkably, few studies have included individuals from this region, hindering the examination of chimpanzee population structure across Africa. Here, we analyzed microsatellite genotypes of 94 chimpanzees, including 32 designated as P. t. ellioti. We find that chimpanzees fall into three major populations: (i) Upper Guinea in western Africa (P. t. verus); (ii) the Gulf of Guinea region (P. t. ellioti); and (iii) equatorial Africa (P. t. troglodytes and P. t. schweinfurthii). Importantly, the Gulf of Guinea population is significantly different genetically from the others, sharing a last common ancestor with the populations in Upper Guinea ~0.46 million years ago (mya) and equatorial Africa ~0.32 mya. Equatorial chimpanzees are subdivided into up to three populations occupying southern Cameroon, central Africa, and eastern Africa, which may have constituted a single population until ~0.10-0.11 mya. Finally, occasional hybridization may be occurring between the Gulf of Guinea and southern Cameroon populations.

SUBMITTER: Gonder MK

PROVIDER: S-EPMC3064329 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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Evidence from Cameroon reveals differences in the genetic structure and histories of chimpanzee populations.

Gonder Mary Katherine MK Locatelli Sabrina S Ghobrial Lora L Mitchell Matthew W MW Kujawski Joseph T JT Lankester Felix J FJ Stewart Caro-Beth CB Tishkoff Sarah A SA

Proceedings of the National Academy of Sciences of the United States of America 20110228 12

The history of the genus Pan is a topic of enduring interest. Chimpanzees (Pan troglodytes) are often divided into subspecies, but the population structure and genetic history of chimpanzees across Africa remain unclear. Some population genetics studies have led to speculation that, until recently, this species constituted a single population with ongoing gene flow across its range, which resulted in a continuous gradient of allele frequencies. Chimpanzees, designated here as P. t. ellioti, occu ...[more]

PMID: 21368170

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Evidence from Cameroon reveals differences in the genetic structure and histories of chimpanzee populations.

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Evidence from Cameroon reveals differences in the genetic structure and histories of chimpanzee populations.

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