Copyright © 2002 The American Society of Human Genetics. All rights reserved.
The American Journal of Human Genetics, Volume 71, Issue 5, 1082-1111, 1 November 2002
doi:10.1086/344348
The Making of the African mtDNA Landscape
Antonio Salas1, 2, 3, 
, 
, Martin Richards2, Tomás De la Fe1, María-Victoria Lareu1, Beatriz Sobrino1, Paula Sánchez-Diz1, Vincent Macaulay3 and Ángel Carracedo1
1 Unidad de Genética Forense, Universidad de Santiago de Compostela, Santiago de Compostela, Galicia, Spain
2 Department of Chemical and Biological Sciences, University of Huddersfield, Queensgate, Huddersfield, United Kingdom
3 Department of Statistics, University of Oxford, Oxford
Address for correspondence and reprints: Dr. Antonio Salas, Unidad de Genética Forense, Universidad de Santiago de Compostela, Santiago de Compostela, Galicia, SpainAbstract
Africa presents the most complex genetic picture of any continent, with a time depth for mitochondrial DNA (mtDNA) lineages >100,000 years. The most recent widespread demographic shift within the continent was most probably the Bantu dispersals, which archaeological and linguistic evidence suggest originated in West Africa 3,000–4,000 years ago, spreading both east and south. Here, we have carried out a thorough phylogeographic analysis of mtDNA variation in a total of 2,847 samples from throughout the continent, including 307 new sequences from southeast African Bantu speakers. The results suggest that the southeast Bantu speakers have a composite origin on the maternal line of descent, with ∼44% of lineages deriving from West Africa, ∼21% from either West or Central Africa, ∼30% from East Africa, and ∼5% from southern African Khoisan-speaking groups. The ages of the major founder types of both West and East African origin are consistent with the likely timing of Bantu dispersals, with those from the west somewhat predating those from the east. Despite this composite picture, the southeastern African Bantu groups are indistinguishable from each other with respect to their mtDNA, suggesting that they either had a common origin at the point of entry into southeastern Africa or have undergone very extensive gene flow since.
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