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eastara
06-19-2019, 11:00 AM
In the latest Chinese study, which tries to disprove the Out of Africa theory, they discuss the possibilities of other configurations of Y and mito haplogroup trees, where the African haplogroups are not in the root, but rather those from Eastern Eurasia.
https://www.biorxiv.org/content/10.1101/101410v6.full

As far as I understood regarding the Y tree, the most basal haplogroup is supergroup F, while the African are only a small branch. It seems they got to that configuration taking in mind the repeating mutation if different haplogroups. The official classification explains that with independent mutations in different branches however the Chinese claim that these are in fact the common mutation of the most basal haplogroup.
Is there any merit in their claims, has somebody tried to make other tree configurations based on a different approach?

The existing Y phylogenetic tree depends on inferring derived alleles and in turn requires the validity of the infinite site assumption, which means no maximum genetic distance and no recurrent mutations. However, this assumption can be proven invalid even just by the existing Y tree itself, since the tree shows numerous recurrent mutations that were simply ignored without valid reasons (Supplementary Table S7), especially for the early branches with some such as KxLT and HIJK contradicted by as many as 50% of all relevant SNPs [78]. That these self-contradictions mostly occurred for the early African branches such as BT and CT but rarely for the terminal Eurasian ones indicates the unrealistic nature of these early branches. Also, while haplotypes with few sequence variations from the ancestor of F, C, D, E, NO, KxLT, or K are routinely found in present day people, none could be found for these early branches. The branching pattern in Africans often involves one branch, such as A00, with few or no sub-branches while the other branch A0-T accounting for all of the remaining haplotypes on Earth, which is odd and against branching patterns known in experimental biology such as the embryonic differentiation into three layers with each layer giving rise to multiple cell types.

https://www.biorxiv.org/content/biorxiv/early/2019/06/09/101410/F3.medium.gif