Re: Генетичен атлас за Admixture / Наука / Природни науки / Генетика

Ето пак ви го казват черно на бяло, че имаме сродни гени с другите източноевропейци, които не могат да се обяснят другояче, освен със "славянската" инвазия, като поляци и литовци могат да служат за "прокси".

Shared admixture events in Eastern Europe in the rst Millenium
FineSTRUCTURE did not fully separate groups from Eastern Europe so we repainted them, excluding
each other as donors (\East Europe I" analysis; see Note S7.6).
The two most easterly groups, the Russians and Chuvash, show similar signals of inferred
admixture between two sources, one with ancestry related to Northeast Asians and one related
to Europeans (Table S16). There is evidence in both groups (p<0.05) that this occurred at
more than one time (Figure 2D), with very ancient East Asian ancestry prior to 500BC, in the
case of Russia at least, and a recent event, consistent with approximately Mongol-empire era
admixture, together contributing 10% of DNA in Russians and 35% in the Chuvash.
Six other Eastern European populations show highly shared events (Figure 3). In contrast
to Central Asia, none of these populations shows evidence of multiple admixture times
(p>0.5), but all six independently show evidence for admixture between more than two groups
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(p<0.02). For example in Bulgarian genomes, DNA chunks more closely related to those carried
by present-day Greek, Norwegian and Oroqen people tend to be separated in the genome
so that each pair of curves shows a dip at short genetic distances (Figure 3), implying these
segments must occur on three dierent ancestry backgrounds. The clearest admixture signal in
each population predates the Mongol empire but involves the minority source group having at
least some ancestry related to Northeast Asians (e.g. the Oroqen, Mongola and Yakut), with
2-4% of these groups' total ancestry proportion linking directly to East Asia, lowest in our
Polish sample and highest in Hungarians. A second signal in each group involves admixture
between distinct European and West Eurasian groups { one more southerly (sharing more DNA
segments with e.g. Greece and W. Asia) and one more northerly (sharing more DNA segments
with e.g. North and Northwest Europe) { at approximately the same time as the East Asian
admixture, and with each group inferred as contributing relatively similar amounts of DNA
(though the fraction is uncertain). Inferred admixture dates fall within a relatively tight range
(440-1080CE), earliest in Poland, with groups more distant from Poland generally having more
recent dates. Because this signal is subtle, we constructed one of our coalescent-based admixture
settings to incorporate simultaneous three-way admixture between similarly dierentiated
groups, and at a similar time (36 generations), to those inferred here: encouragingly for our
method's power, GLOBETROTTER accurately determined all three groups given appropriate
source populations (see Notes S5.4-S5.5).
These results are consistent with our detecting a genetic legacy from invasions of peoples
from the Asian steppes (e.g. the Huns, Magyar and Turkic Bulgars) during the rst millennium
CE (31; 38), and aecting all six groups. We speculate that the second event seen in our
six Eastern Europe populations between northern European and southern European ancestral
sources may correspond to the expansion of Slavic language speaking groups (commonly referred
to as the Slavic expansion) across this region at a similar time, perhaps related to displacement
caused by the Eurasian steppe invaders (38; 58). Under this scenario, the northerly source in
the second event might represent DNA from Slavic-speaking migrants (sampled Slavic-speaking
groups are excluded from being donors in the EastEurope I analysis). To test consistency with
this, we repainted these populations adding the Polish as a single Slavic-speaking donor group
(\East Europe II" analysis; see Note S7.6) and, in doing so, they largely replaced the original
North European component (Figure S21), although we note that two nearby populations, Belarus
and Lithuania, are equally often inferred as sources in our original analysis (Table S12).
Outside these six populations, an admixture event at the same time (910CE, 95% CI:720-
1140CE) is seen in the southerly neighboring Greeks, between sources represented by multiple
neighboring Mediterranean peoples (63%) and the Polish (37%), suggesting a strong and early
impact of the Slavic expansions in Greece, a subject of recent debate (37). These shared signals
we nd across East European groups could explain a recent observation of an excess of IBD
sharing among similar groups, including Greece, that was dated to a wide range between 1,000
and 2,000 years ago (37)