@lukas,
Where is it said or implied by the authors that those ethnic groups are in the same genetic cluster? That isn't what they're saying. You have to understand the terms that geneticists use or else you won't understand the papers.
Ok. I have discussion about it on anthrogenica. Here the opinions.
Originally Posted by
lukaszM 
How do you explain very atypical Polish, Welsh, Tuscan and South Italian affinity on above map
I mean red color in those places. There is no way Poles and Welshmen, or Polish and Tuscan, or Polish and Basilicate could be in one, autosomal cluster.
Michał
I need to agree with Tomenable on this. Depending on which specific kind of Y-DNA analysis you are applying, the results may point to different populations. Let's imagine that you have one relatively old ancestral population, for example the Urnfield culture or the Danubian Tumulus culture, and a younger culture that descended from that older culture, for example the Lusatian/Kyjatice culture. Let's then imagine that this younger Lusatian/Kyjatice culture got practically extinct, with only a very small part of its original population contributing to modern populations (mostly in Poland, but occasionally elsewhere, including for example Italy). On the other hand, that older ancestral population (Urnfield or Tumulus) contributed very significantly to many different populations in Europe, mostly in the Upper Danubian (or North Alpine) region but also in the Balkans and in Western Europe. Since BR2 descended from Urnfield/Tumulus but its own descending population got nearly extinct, every test that looks for just an overall similarity (ie. for a
proportion of similar ancestry) will point to those modern countries that descend in largest part from Urnfield/Tumulus, and this will include Austria, all of Germany, large part of France, Northern Italy, Western Balkans, and even a part of Britain. On the other hand, when applying the haplotype affinity-based assay based on the BR2 sample from the Lusatian/Kyjatice culture, you will preferentially identify those modern populations that descend "directly" from this younger ancient population, so the time distance from the direct ancestral population was smaller and the haplotypes (ie. the groups of neighboring markers/mutations/SNPs) were more likely to survive intact, instead of being separated by the random recombination events, even though the overall contribution of the BR2-like DNA was relatively small.
This is similar to a situation with the descendants of Thomas Jefferson. When placing all Americans on an autosomal PCA plot, all white people who don't descend from Jefferson will land up much closer to Jefferson than his direct black descendants, while when using the FTDNA Family Finder test (which is a kind of a haplotype-based affinity test) you will preferentially identify those who are his direct descendants (or descendants of his very close relatives).
Originally Posted by
Michał
This is similar to a situation with the descendants of Thomas Jefferson. When placing all Americans on an autosomal PCA plot, all white people who don't descend from Jefferson will land up much closer to Jefferson than his direct black descendants, while when using the FTDNA Family Finder test (which is a kind of a haplotype-based affinity test) you will preferentially identify those who are his direct descendants (or descendants of his very close relatives).
lukaszM
But autosomally (in the sense of autosomal components, even those basic like WHG, EEF, SSA, EAst-Asian etc.) those white Americans are really more close to Jefferson than his mulatto descendants. It's true.
I'm really doubt BR2 direct descendants are really so numerous to be present in such large quantity to be substantial portion of Polish ancestry. It was some Kyatice harem where BR2 sultan had 500 wives?
I have much simpler explanation. BR2 was chosen by ancient oracle because mediated by RISE598 gives more or less something comparable to present Poles. Simply becasue of lack of directly similar sample to Polish population.
Austria + Lithuania /2 = south-central Poland.
Originally Posted by
lukaszM
But autosomally (in the sense of autosomal components, even those basic like WHG, EEF, SSA, EAst-Asian etc.) those white Americans are really more close to Jefferson than his mulatto descendants. It's true.
Michał
This is correct, and also the modern Austrians, Germans and French people are "autosomally" much closer to BR2 than modern Poles, in case you discuss this question from this very perspective. However, there is also no doubt that those black descendants of Jefferson are his "much closer relatives" (in the genealogical sense) than the vast majority of modern white Americans, and the same might apply to modern Poles and BR2.
Originally Posted by
lukaszM
I'm really doubt BR2 direct descendants are really so numerous to be present in such large quantity to be substantial portion of Polish ancestry.
Michał
You might be right about it, as there is a substantial risk that those results for the haplotype affinity-based analysis show only some kind of statistical noise (just like it frequently happens with the Family Finder results for some putative "remote cousins"). However, the relatively good quality of BR2 suggests its affinity to modern Poles might be real, and we won't be able to definitely verify it until some good quality Polish samples for the Lusatian culture are available (although the incoming results for Przeworsk and Wielbark should also be helpful in this respect).
Originally Posted by
lukaszM
I have much simpler explanation. BR2 was chosen by ancient oracle becasue mediated by RISE598 gives more or less something comaprable to present Poles. Simply becasue of lack of directly similar sample to Polsih population.
Austria + Lithuania /2 = south-central Poland.
Michał
This might be true, although I suspect that what affects those oracle results most strongly is rather a lack of an ancient sample from a yet unknown BR2-like Iron Age (or Roman times) population that significantly contributed to the Early Slavs. Anyway, I'm afraid that all this has nothing to do with those haplotype-based affinity analysis results, as these two tests investigate two very different aspects of the BR2-related ancestry.
