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LeBrok
03-01-14, 22:41
From recent paper:


Table S12.10: European populations that cannot be fit as a 3-way mix of EEF, WHG, and ANE
Population Violated statistic fitted estimated Z
Finnish Karitiana, MA1; Loschbour, Finnish 0.002025 -0.003984 -3.161
Mordovian Karitiana, MA1; Loschbour, Mordovian 0.002050 -0.004990 -3.790
Russian Karitiana, MA1; Loschbour, Russian 0.001947 -0.004214 -3.398

In Extended Data Fig. 6 we plot f4(Test, BedouinB; Han, Mbuti) and f4(Test, BedouinB; MA1, Mbuti)
statistics; we use BedouinB so that we can also plot Stuttgart in the same figure. Populations that fit
the model of Fig. S12.11 form a clear cline from Stuttgart in the south, to Lithuanians and Estonians
in the north, but the three populations violating our model (Table S12.10) are clearly to the right,
sharing relatively more common drift with the Han. We also add the single Saami individual from our
dataset and the Chuvash on this plot, two additional European groups who deviate from the main

European cline even more strongly in the same direction.
While we see no evidence that the Han have West Eurasian admixture (SI 9), it is still possible that
they possess some unknown common component with Northeast Europeans. We also calculated the
f3(Mbuti; Atayal, Test) statistic for West Eurasian populations which measures the amount of
common drift between Atayal (a Taiwanese aboriginal population that seems extremely unlikely to
have historical connections with Northeastern Europeans in particular) and plot it in Figure S12.18.
Northeastern Europeans share higher amounts of drift with Atayal as well, consistent with having an
east Eurasian influence that is lower (or lacking) in other Europeans.


. However, we think that the genetic landscape Siberia has changed since the time of MA1
(~24,000 years ago), as this would explain both the fact that present-day Siberians share less drift with
MA1 than both Europeans and Native Americans11



Conversely, we do not currently know whether the signal of admixture observed in the Near East and
Caucasus reflects an arrival of MA1-related ancestry from the east, or alternatively dilution of native
MA1-related ancestry by an expansion of a Near Eastern population carrying Basal Eurasian



More interesting thoughts, but a bit off topic. (couldn't resist :) )

Concluding Remarks
We chose to model the 3-way admixture as taking place in the order (Early European Farmers, (West
European Hunter Gatherers, Ancient North Eurasians)), but we should caution that the order is
unknown and may become apparent as later samples from Europe and elsewhere provide ancient
DNA for study


A geographically parsimonious hypothesis would be that a major component of present-day European
ancestry was formed in eastern Europe or western Siberia where western and eastern hunter-gatherer
groups could plausibly have intermixed. Motala12 has an estimated WHG/(WHG+ANE) ratio of 81%
(S12.7), higher than that estimated for the population contributing to modern Europeans



Conversely, we assumed that “Hunter”
was composed only of WHG/ANE ancestry, but it is possible that the actual population that admixed
with EEF may have already possessed EEF ancestry itself.

http://arxiv.org/ftp/arxiv/papers/1312/1312.6639.pdf


Did anyone find additional information about this admixture? Does it have a name?

Petter
06-01-14, 10:58
I think it is very likely that it is so. I have always argued for that there are components in Central Eurasia that can neither be classified as caucasoid nor mongoloid, in fact I think there is an obsession with only two races among some people. There most also be unique genes in between, as all of Eurasia has been populated for a very long time.