"E-M183 (E-M81) is the most frequent paternal lineage in North Africa and thus it must be considered to explore past historical and demographical processes. Here, by using whole Y chromosome sequences from 32 North African individuals, we have identified five new branches within E-M183. The validation of these variants in more than 200 North African samples, from which we also have information of 13 Y-STRs, has revealed a strong resemblance among E-M183 Y-STR haplotypes that pointed to a rapid expansion of this haplogroup. Moreover, for the first time, by using both SNP and STR data, we have provided updated estimates of the times-to-the-most-recent-common-ancestor (TMRCA) for E-M183, which evidenced an extremely recent origin of this haplogroup (2,000–3,000 ya). Our results also showed a lack of population structure within the E-M183 branch, which could be explained by the recent and rapid expansion of this haplogroup. In spite of a reduction in STR heterozygosity towards the West, which would point to an origin in the Near East, ancient DNA evidence together with our TMRCA estimates point to a local origin of E-M183 in NW Africa."
Studies based on the Y chromosome have highlighted E-M78 and E-M81 as the most frequent paternal lineages in North Africa, although they showed different distribution patterns. Whereas the frequency of E-M78 declines towards Northwest Africa, E-M81 has been found at high frequencies (71%) in Northwestern Africa and its frequency decreases towards the East; it is found sporadically in S Europe and E Africa, and it is practically absent elsewhere. These evidences suggest that E-M81 must be considered to explore the historical and demographical processes that gave rise to current North African populations. However, little is known about the phylogeographic structure of this haplogroup and its origin and emergence are still very controversial. While some studies pointed to a Palaeolithic origin21, other authors claimed that E-M81 may have a Neolithic origin22. The most likely scenario, as suggested by Fadhlaoui-Zid et al.17, is that the origin of E-M81 is more recent than previously reported.
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