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Harkonnen
09-01-2019, 09:43 PM
As should be known, SHGs were very light pigmented compared to WHGs and EHGs (which they were a mix of). They also show adaptation to cold environments in gene regions associated with physical performance.


With the aim of detecting signs of adaptation to high-latitude environments and selection during and after the Mesolithic period, we employed two different approaches that utilize the Mesolithic genomic data. In the first approach, we assumed that SHGs adapted to high-latitude environments of low temperatures and seasonally low levels of light, and searched for gene variants that carried over to modern-day people in northern Europe.

We designed a statistic, Dsel (S9 Text), that captures this specific signal and scanned the whole genome for gene variants that show strong continuity (little differentiation) between SHGs and modern-day northern Europeans while exhibiting large differentiation to modern-day southern European populations [46] (Fig 4A; S9 Text). Six of the top 10 SNPs with greatest Dsel values were located in the TMEM131 gene that has been found to be associated with physical performance [47], which could make it part of the physiological adaptation to cold [48]. This genomic region was more than 200 kbp (kilo base pairs) long and showed the strongest haplotypic differentiation between modern-day Tuscan individuals (TSIs) and modern-day Finnish individuals (FINs) across the genome (S9 Text). The particular haplotype was relatively common in SHGs, it is even more common among today’s Finnish population (S9 Text) and showed a strong signal of local adaptation (S9 Text). Other top hits included genes associated with a wide range of metabolic, cardiovascular, and developmental and psychological traits (S9 Text) potentially linked to physiological adaptation to cold environments [48].

Snkves
09-01-2019, 10:05 PM
And EDAR, lots of EDAR.

https://i.imgur.com/EyednQJ.png

https://i.imgur.com/7SnYfMU.png


Compared to:
https://i.imgur.com/5Z5KeRX.png

Harkonnen
09-01-2019, 10:20 PM
Indeed, Scandinavian Hunter Gatherers had loads of EDAR. I have a actually theory, that it is quite possible that EDAR-mutation first happend in ANE population. As can be seen even in those charts you posted the hotspot of EDAR is in the Americas, and it goes somewhat down towards South East Asia. Of course it is also possible that the ENA admixture in EHG is responsible for the high EDAR in SHG. The mutation just for some reason spread like wildfire in Mesolithic Scandinavia. Interesting is also that Komi-Zyrians completely lack EDAR mutation -- even Greeks have some.