60,000 years of interactions between Central and Eastern Africa documented by major African mitochondrial haplogroup L2

• Autor(a) principal: Silva, M
• Data de Publicação: 2015
• Outros Autores: Alshamali, F, Silva, P, Carrilho, C, Mandlate, F, Trovoada, MJ, Cerny, V, Pereira, L, Soares, P
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10216/109278
• topic: Africa Central; Africa Eastern; African Continental Ancestry Group/genetics; African Continental Ancestry Group/history; Base Sequence; DNA Mitochondrial/genetics; DNA Mitochondrial/history; Emigration and Immigration/history; Evolution, Molecular; Haplotypes/genetics; History; 15th Century; History; 16th Century; History 17th Century; History 18th Century; History 19th Century; History 20th Century; History 21st Century; History Medieval; Humans; Molecular Sequence Data; Polymorphism Single Nucleotide/genetics

Mitochondrial DNA (mtDNA) haplogroup L2 originated in Western Africa but is nowadays spread across the entire continent. L2 movements were previously postulated to be related to the Bantu expansion, but L2 expansions eastwards probably occurred much earlier. By reconstructing the phylogeny of L2 (44 new complete sequences) we provide insights on the complex net of within-African migrations in the last 60 thousand years (ka). Results show that lineages in Southern Africa cluster with Western/Central African lineages at a recent time scale, whereas, eastern lineages seem to be substantially more ancient. Three moments of expansion from a Central African source are associated to L2: (1) one migration at 70-50 ka into Eastern or Southern Africa, (2) postglacial movements (15-10 ka) into Eastern Africa; and (3) the southward Bantu Expansion in the last 5 ka. The complementary population and L0a phylogeography analyses indicate no strong evidence of mtDNA gene flow between eastern and southern populations during the later movement, suggesting low admixture between Eastern African populations and the Bantu migrants. This implies that, at least in the early stages, the Bantu expansion was mainly a demic diffusion with little incorporation of local populations.