Admixture into and within sub-Saharan Africa

George Bj Busby (1) , Gavin Band (1, 2) , Quang Si Le (1) , Muminatou Jallow (3) , Edith Bougama (4) , Valentina Mangano (5) , Lucas Amenga-Etego (6) , Anthony Enimil (7) , Tobias Apinjoh (8) , Carolyne Ndila (9) , Alphaxard Manjurano (10) , Vysaul Nyirongo (11) , Ogobara Doumba (12) , Kirk Rockett (1, 2) , Dominic Kwiatkowski (1, 2) , Chris Ca Spencer (1) , Malaria Genomics Epidemiology Network Collaborators (273) (1, 2, 13)

1 The Wellcome Trust Centre for Human Genetics [Oxford]
2 The Wellcome Trust Sanger Institute [Cambridge]
3 MRC - Medical Research Council Unit The Gambia
4 CNRFP - Centre National de Recherche et de Formation sur le Paludisme [Ouagadougou, Burkina Faso]
5 UNIROMA - Università degli Studi di Roma "La Sapienza" = Sapienza University [Rome]
6 NHRC - Navrongo Health Research Centre [Navrongo, Ghana]
7 Komfo Anokye Teaching Hospital
8 University of Buéa
9 KWTRP - KEMRI-Wellcome Trust Research Programme
10 LSHTM - London School of Hygiene and Tropical Medicine
11 University of Malawi
12 University of Bamako [Mali]
13 Institut Pasteur de Dakar

Similarity between two individuals in the combination of genetic markers along their chromosomes indicates shared ancestry and can be used to identify historical connections between different population groups due to admixture. We use a genome-wide, haplotype-based, analysis to characterise the structure of genetic diversity and gene-flow in a collection of 48 sub-Saharan African groups. We show that coastal populations experienced an influx of Eurasian haplotypes over the last 7000 years, and that Eastern and Southern Niger-Congo speaking groups share ancestry with Central West Africans as a result of recent population expansions. In fact, most sub-Saharan populations share ancestry with groups from outside of their current geographic region as a result of gene-flow within the last 4000 years. Our in-depth analysis provides insight into haplotype sharing across different ethno-linguistic groups and the recent movement of alleles into new environments, both of which are relevant to studies of genetic epidemiology.

Mots clés: Africa; admixture; chromosome painting; evolutionary biology; gene-flow; genomics; human

Domaines: Bio-informatique [q-bio.QM]; Bio-Informatique, Biologie Systémique [q-bio.QM]; Génétique humaine; Génétique des populations [q-bio.PE]; Virologie; Parasitologie; Santé publique et épidémiologie

George Bj Busby, Gavin Band, Quang Si Le, Muminatou Jallow, Edith Bougama, et al.. Admixture into and within sub-Saharan Africa. eLife, 2016, 5, pp.e15266. ⟨10.7554/eLife.15266⟩. ⟨pasteur-02003953⟩