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Comment by robwwilliams | Hacker News Reader

One error in this article by Zimmer that surprises me. He claims all modern humans have some admixture with Neaderthals but to the best of my knowledge this is not true of KhoiSan, Central African hunter gatherers, and several West African populations.

Does Zimmer know something that I do not? Or David Reich?

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Hasn't backmigration/Eurasian admixture post-introgression made that true? iirc reference bias artefactually made African genomes look like they had no Neanderthal segments.

https://www.cell.com/cell/fulltext/S0092-8674(20)30059-3 https://www.pnas.org/doi/full/10.1073/pnas.1313787111

Lovely paper but their analysis did not include either KhoiSan or Central African hunter-gather Pygmy populations. They used the 1000 Genomes project.

I read a bit more. There definitely was introgression of West Eurasian populations into East Africa and Sudan than percolated into West Africans to the tune of about 15 million base-pairs of sequence tagged as Neanderthal. Not sure we have values for how much Yoruban ancestry is now embedded in Mbuti genomes, but it is small. So the flow of Neanderthal genomes into Central African hunter-gathers will sub-decimal dust.

But having said all that, maybe the key point Zimmer is making IS a good generalization.

I think it is a fair generalization at this point. Mbuti also have a ~6% West Eurasian admixture signal using an ancient (4.5kya) Ethiopian individual as reference, though Pickrell 2014 did not see it. Decimal dust, perhaps? https://www.science.org/doi/10.1126/science.aad2879

The ghost admixture story(s) will turn out to be much more localized, I imagine.

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