The Making of the African mtDNA Landscape
Antonio Salas,1,2,3 Martin Richards,2 Toma´s De la Fe,1 Marı´a-Victoria Lareu,1 Beatriz Sobrino,1
Paula Sa´nchez-Diz,1 Vincent Macaulay,3 and ngel Carracedo1
1Unidad de Gene´tica Forense, Universidad de Santiago de Compostela, Santiago de Compostela, Galicia, Spain; 2Department of Chemical
and Biological Sciences, University of Huddersfield, Queensgate, Huddersfield, United Kingdom; and 3Department of Statistics, University of
Oxford, Oxford
Africa presents the most complex genetic picture of any continent, with a time depth for mitochondrial DNA
(mtDNA) lineages 1100,000 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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