The discovery of two SNPs (V38 and V100) by Trombetta et al. (2011) significantly redefined the E-V38 phylogenetic tree. This led the authors to suggest that E-V38 may have originated in East Africa. V38 joins the West African-affiliated E-M2 and the Northeast African-affiliated E-M329 with an earlier common ancestor who, like E-P2, may have also originated in East Africa.[2] The downstream SNP E-M180 may have originated in the humid south-central Saharan savanna/grassland of North Africa between 14,000 BP and 10,000 BP.[4][5][6][7] According to Wood et al. (2005) and Rosa et al. (2007), such population movements changed the pre-existing population Y chromosomal diversity in Central, Southern, and SoutheasternAfrica, replacing the previous haplogroup frequencies (haplogroups A and B-M60) in these areas with the now dominant E1b1a1 lineages. Traces of earlier inhabitants, however, can be observed today in these regions via the presence of the Y DNA haplogroups A1a, A1b, A2, A3, and B-M60 that are common in certain populations, such as the Mbuti and Khoisan.[8][9][10] Shriner et al. (2018) similarly suggests that haplogroup E1b1a-V38 traversed across the Green Sahara from east to west around 19,000 years ago, where E1b1a1-M2 may have subsequently originated in West Africa or Central Africa. Shriner et al. (2018) also traces this movement via sickle cell mutation, which likely originated during the Green Sahara period.[3]
E-V38's frequency and diversity are highest in West Africa. Within Africa, E-V38 displays a west-to-east as well as a south-to-north clinal distribution. In other words, the frequency of the haplogroup decreases as one moves from western and southern Africa toward the eastern and northern parts of Africa.[13]
Prior to 2002, there were in academic literature at least seven naming systems for the Y-Chromosome Phylogenetic tree. This led to considerable confusion. In 2002, the major research groups came together and formed the Y-Chromosome Consortium (YCC). They published a joint paper that created a single new tree that all agreed to use. Later, a group of citizen scientists with an interest in population genetics and genetic genealogy formed a working group to create an amateur tree aiming at being above all timely. The table below brings together all of these works at the point of the landmark 2002 YCC Tree. This allows a researcher reviewing older published literature to quickly move between nomenclatures.
This phylogenetic tree of haplogroup subclades is based on the Y-Chromosome Consortium (YCC) 2008 Tree,[16] the ISOGG Y-DNA Haplogroup E Tree,[5] and subsequent published research.
^Van Oven M, Van Geystelen A, Kayser M, Decorte R, Larmuseau HD (2014). "Seeing the wood for the trees: a minimal reference phylogeny for the human Y chromosome". Human Mutation. 35 (2): 187–91. doi:10.1002/humu.22468. PMID24166809. S2CID23291764.
^K-M2313*, which as yet has no phylogenetic name, has been documented in two living individuals, who have ethnic ties to India and South East Asia. In addition, K-Y28299, which appears to be a primary branch of K-M2313, has been found in three living individuals from India. See: Poznik op. cit.; YFull YTree v5.08, 2017, "K-M2335", and; PhyloTree, 2017, "Details of the Y-SNP markers included in the minimal Y tree" (Access date of these pages: 9 December 2017)
^ Haplogroup S, as of 2017, is also known as K2b1a. (Previously the name Haplogroup S was assigned to K2b1a4.)
^ Haplogroup M, as of 2017, is also known as K2b1b. (Previously the name Haplogroup M was assigned to K2b1d.)
^Montano, Valeria; Gianmarco Ferri; Veronica Marcari; Chiara Batini; Okorie Anyaele; Giovanni Destro-Bisol; David Comas (1 July 2011). "The Bantu expansion revisited a new analysis of Y chromosome variation in Central Western Africa". Molecular Ecology. 20 (13): 2693–2708. doi:10.1111/j.1365-294X.2011.05130.x. PMID21627702. S2CID9951365.
Underhill, Peter A.; Shen, Peidong; Lin, Alice A.; Jin, Li; et al. (November 2000). "Y chromosome sequence variation and the history of human populations". Nature Genetics. 26 (3): 358–361. doi:10.1038/81685. PMID11062480. S2CID12893406.