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View Full Version : 60,000 years of interactions in Africa shown by mtDNA haplogroup L2



Piquerobi
08-06-2015, 05:56 PM
Interestingly, by looking at mtDNA haplogroup L2, the researchers have inferred three moments of expansion from a Central African source are associated to L2: (1) one migration at 7050 ka into Eastern or Southern Africa, (2) postglacial movements (1510 ka) into Eastern Africa; and (3) the southward Bantu Expansion in the last 5 ka. Does anyone know more about (1) and (2) expansions?


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

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 7050 ka into Eastern or Southern Africa, (2) postglacial movements (1510 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.
http://www.nature.com/srep/2015/150727/srep12526/full/srep12526.html

RCO
08-07-2015, 01:18 PM
That's a very important article. The ethnic origins of L2 haplotypes depends on the accumulation of critical mass of data. We can observe the association of haplotypes with ethnic groups here:
http://www.nature.com/article-assets/npg/srep/2015/150727/srep12526/extref/srep12526-s2.xls
We need to collect more data for its study !

Kale
08-07-2015, 03:15 PM
The L2a1 in neolithic middle east and it being the dominant type of L in Europe raises some questions as well. North Africa is going to be a lot more important than we give it credit for once some ancient DNA arrives.