One of the things that I’ve always been curious about is why some Indian populations are not fairer in complexion if they had so much steppe. The logic here is that the “most steppe population” are peoples such as the Lithuanians, and these are very fair-skinned groups. If, for example, North Indian Brahmins were ~30% steppe, and these steppe people looked like Lithuanians, wouldn’t we see more blondes in northern India?
I’ve posted on this before, but after today’s conversation with Vagheesh, I checked the data on his Sintashta samples on the Hiris-Plex pigmentation panel. Pigmentation prediction in ancient populations are pretty sketchy…but the Sintashta are actually not that different from many modern Northeast Europeans.
Spot-checking some major loci where Europeans are very distinct, such as KITLG, OCA2-HERC2, and SLC45A2, it is clear to me that the Sintashta were much more darkly complected than modern Northern Europeans.
To give a concrete example, rs16891982 in SLC45A2 is at 2% minor allele frequency in British 1000 Genomes samples (3% in Tuscans, 18% in Spaniards). The minor allele frequency is 12.5% in 64 Sintashta chromosomes.
The derived SNP associated with blonde hair in Northern Europeans, and found at about 20% frequency in those populations, was found in none of the 32 calls where that position was returned.
I doubt the Sintashta were very dark. Rather, their pigmentation was probably more in the range of Southern Europeans like Sardinians if I had to bet.
(one of the implications here is that the results which indicate strong selection for lighter complexion in Northern Europeans into historical times are probably detecting something real)
|Sintashta MLBA on HirisPlex|