Substack cometh, and lo it is good. (Pricing)

Neutral…going…going…gon….Wait!!!

Mitochondrial DNA variants linked to renal, prostate cancer.

Via Dienekes.

Related: Saami and berbers-an unexpected mitochondrial DNA link. The mitochondrial DNA link is a clade within haplgroup U, the mtDNA variant which might result in the negative selection pressure noted above. Abstract:

Intriguingly, the Saami of Scandinavia and the Berbers of North Africa were found to share an extremely young branch, aged merely ∼9,000 years. This unexpected finding not only confirms that the Franco-Cantabrian refuge area of southwestern Europe was the source of late-glacial expansions of hunter-gatherers that repopulated northern Europe after the Last Glacial Maximum but also reveals a direct maternal link between those European hunter-gatherer populations and the Berbers.

I’ve talked about the Iberian refugia multiple times, but generally I have been skeptical of a Berber connection because of various studies, including a recent one that carries the title A Predominantly Neolithic Origin for Y-Chromosomal DNA Variation in North Africa. But though the Saami display a particular DNA motif at frequencies of near 50%, among the Berbers the frequency is exhibited in the range of ~2% (similar to populations of southwestern Europe). The above link indicates that negative selection might have played some role in reducing the frequency of this haplogroup. It might be that the fitness hit might have impacted Saami and the peoples of southwestern Europe and northern Africa differently (the environments and diets are very different). Additionally, I don’t know how much credit to put in the Saami frequencies since bottleneck effects are attributed to this population (in the far north of Europe with a specialized lifestyle they inhabit a functional genetic island). Nevertheless, the presence of a high frequency of a haplogroup whose origin is likely in Iberia in northern Scandinavia adds a layer of complexity to our perception of European demographic pasts, while the possibility of selection muddles it even further….

Posted by razib at 09:00 PM

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