Saturday, August 8, 2015

New Paper about the Phylogeny of Haplogroup E

Trombetta et al.


Abstract:


Haplogroup E, defined by mutation M40, is the most common human Y chromosome clade within Africa. To increase the level of resolution of haplogroup E, we disclosed the phylogenetic relationships among 729 mutations found in 33 haplogroup DE Y-chromosomes sequenced at high coverage in previous studies. Additionally, we dissected the E-M35 subclade by genotyping 62 informative markers in 5,222 samples from 118 worldwide populations. The phylogeny of haplogroup E showed novel features compared to the previous topology, including a new basal dichotomy. Within haplogroup E-M35, we resolved all the previously known polytomies and assigned all the E-M35* chromosomes to 5 new different clades, all belonging to a newly identified subhaplogroup (E-V1515), which accounts for almost half of the E-M35 chromosomes from the Horn of Africa. Moreover, using a Bayesian phylogeographic analysis and a SNP-based approach we localized and dated the origin of this new lineage in the northern part of the Horn, about 12 kya. Time frames, phylogenetic structuring and socio-geographic distribution of E-V1515 and its subclades are consistent with a multi-step demic spread of pastoralism within north-eastern Africa and its subsequent diffusion to sub-equatorial areas. In addition, our results increase the discriminative power of the E-M35 haplogroup for use in forensic genetics through the identification of new ancestry-informative markers.


Link to study




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