PT  - JOURNAL ARTICLE
AU  - Vladimir Bajić
AU  - Chiara Barbieri
AU  - Alexander Hübner
AU  - Tom Güldemann
AU  - Christfried Naumann
AU  - Linda Gerlach
AU  - Falko Berthold
AU  - Hirosi Nakagawa
AU  - Sununguko W. Mpoloka
AU  - Lutz Roewer
AU  - Josephine Purps
AU  - Mark Stoneking
AU  - Brigitte Pakendorf
TI  - Genetic structure and sex-biased gene flow in the history of southern African populations
AID  - 10.1101/237297
DP  - 2017 Jan 01
TA  - bioRxiv
PG  - 237297
4099  - http://biorxiv.org/content/early/2017/12/21/237297.short
4100  - http://biorxiv.org/content/early/2017/12/21/237297.full
AB  - Objectives We investigated the genetic history of southern African populations with a special focus on their paternal history. We reexamined previous claims that the Y-chromosome haplogroup E1b1b was brought to southern Africa by pastoralists from eastern Africa, and investigated patterns of sex-biased gene flow in southern Africa.Material and Methods We analyzed previously published complete mtDNA genome sequences and ~900 kb of NRY sequences from 23 populations from Namibia, Botswana and Zambia, as well as haplogroup frequencies from a large sample of southern African populations and 23 newly genotyped Y-linked STR loci for samples assigned to haplogroup E1b1b.Results Our results support an eastern African origin for Y-chromosome haplogroup E1b1b; however, its current distribution in southern Africa is not strongly associated with pastoralism, suggesting a more complex origin for pastoralism in this region. We confirm that the Bantu expansion had a notable genetic impact in southern Africa, and that in this region it was probably a rapid, male-dominated expansion. Furthermore, we find a significant increase in the intensity of sex-biased gene flow from north to south, which may reflect changes in the social dynamics between Khoisan and Bantu groups over time.Conclusions Our study shows that the population history of southern Africa has been very complex, with different immigrating groups mixing to different degrees with the autochthonous populations. The Bantu expansion led to heavily sex-biased admixture as a result of interactions between Khoisan females and Bantu males, with a geographic gradient which may reflect changes in the social dynamics between Khoisan and Bantu groups over time.