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Angela
09-09-16, 15:20
Y-chromosomal sequencing and screening reveal both stability and migrations in North Eurasian populations. Balanovsky et alhttps://ep70.eventpilot.us/web/page.php?page=IntHtml&project=ASHG16&id=160121213

"Y-chromosomal markers exhibit the highest interpopulation diversity in the genome and thus form one of the most informative tools for tracing population history. However, their information value depends on discovering SNPs which subdivide haplogroups with broad geographic distribution into branches revealing fine population structure. Progress in such discoveries has recently moved from a slow linear phase to a rapid exponential phase due to NGS.

We applied this approach to the Y-chromosomal pool of North Eurasian populations and concentrated on haplogroups C, G1, G2, N1b, N1c, and R1b. We sequenced 181 Y-chromosomes (capturing 11 Mb from each sample), developed the NGSConv software for calling Y-chromosomal SNPs, and identified roughly 2,500 SNPs, most of which were new. Then we constructed phylogenetic trees and dated dozens of their branches using our estimates of the mutation rate. The last – but not the least – step included screening branch-defining SNPs in the entire Biobank of indigenous North Eurasian populations (led by prof. Elena Balanovska), which includes 26,000 samples from 260 populations. This screening resulted in frequency distribution maps of 29 branches of haplogroups R1b and C, thus increasing the phylogenetic resolution by an order of magnitude compared to the two initial haplogroups.

For haplogroup R1b, we identified a previously unstudied “eastern” branch, R1b-GG400, found in East Europeans and West Asians and forming a brother clade to the “western” branch R1b-L51 found in West Europeans. The ancient samples from the Yamnaya archaeological culture are located on this eastern branch, showing that the paternal descendants of the Yamnaya population – in contrast to the published autosomal findings - still live in the Pontic steppe and were not an important source of paternal lineages in present-day West Europeans.

For haplogroup C-M217 - the predominant paternal component in Central Asians - we found signals of simultaneous expansion in two independent branches. Both expansion times and gene geographic maps of the expanded lineages indicated the emergence of the Mongol Empire as the likely trigger.

We conclude that simply discovering new SNP is not enough, but in combination with screening for the branch-defining SNPs in large biobanks of indigenous populations, it allows comprehensive reconstruction of male population history.
The study was supported by the Russian Science Foundation grant 14-14-00827 to OB."

That seems like a rather sweeping generalization to draw from the data in terms of R1b, although of course we have to wait and see the paper itself.

If the brother clade of L51 is in the Yamnaya samples we have, why wouldn't it be likely that L51 is west of that in the still largely unsampled areas of western Yamnaya?

bicicleur
09-09-16, 17:16
this will be interesting because it is mostly unchatered territory

the abstract does not say how old the sampled DNA is

could the newly discovered R1b branch be the Afanasievo people?

Tomenable
09-09-16, 17:43
Oleg Balanovsky has just announced that he discovered a new branch of L23 - GG400, a "brother" of L51 and Z2103.

Up to this point, we used to divide all of R1b-L23+ into just two major branches (Western defined by L51 and Eastern defined by Z2103), while all lineages positive for L23 but negative for both L51 and Z2103 mutations, used to be classified as basal or unresolved L23*. It turns out, that at least some part of this basal or until now unresolved L23* can be classified as belonging to a newly discovered branch defined by SNP called GG400. From now on, we will have not just two, but three main branches of L23+, namely: L23>L51, L23>Z2103 and L23>GG400. It seems, that this GG400 branch is concentrated mainly in Eastern Europe and probably a large part of basal or unresolved L23* samples (negative for L51 and Z2103) from FTDNA Polish Project will turn out to be under L23>GG400.

In total few (four or five) percent of ethnic Poles are either L23>Z2103, L23>GG400 or other L23* negative for L51.

Another typically Eastern European branch of Non-L51 is L23>Z2103>Y5587 ("EE Type" in FTDNA Polish Project).

===========================================

Read more: https://ep70.eventpilot.us/web/page.php?page=IntHtml&project=ASHG16&id=160121213

According to this information, ancient L23* from Yamnaya that was negative for Z2103, was most likely GG400.

bicicleur
09-09-16, 18:45
tomenable, please look and continue in this thread :

http://www.eupedia.com/forum/threads/32765-Upcoming-paper-on-yDna-of-North-Eurasia

Tomenable
09-09-16, 19:21
Can we merge both threads?:

http://www.eupedia.com/forum/threads/32769-R1b-L23-gt-GG400-a-brand-new-(!)-branch-of-L23-brotherly-to-L51-and-Z2103

MarkoZ
09-09-16, 19:40
That seems like a rather sweeping generalization to draw from the data in terms of R1b, although of course we have to wait and see the paper itself.

If the brother clade of L51 is in the Yamnaya samples we have, why wouldn't it be likely that L51 is west of that in the still largely unsampled areas of western Yamnaya?

A linear descent of European R1b from Yamnaya was never feasible, hence the ad hoc hypothesis of continuous incursions from the Eastern European grasslands into the central Balkans for which there is no archeological evidence.

Tomenable
09-09-16, 19:45
MarkoZ,


A linear descent of European R1b from Yamnaya was never feasible

It was, and still is, feasible. Angela is right.

The fact that 2 out of 3 branches of L23 are found in Yamnaya - both Z2103 and newly discovered GG400 - makes it even more probable that L51 was also present in some of Yamnaya sub-groups. This paper actually strengthens the case for "L51 out of Yamnaya".

How do you imagine L51 emerging from L23 in Iberia, when both Z2103 and GG400 emerged from L23 in Russia?

Remember that not much time separates these clades. All of that "children-making" was within several centuries.

The trifurcation of L23 into L51, Z2103 and GG400 most probably took place within the Yamnaya culture.

I used to be against this idea too, but one cannot deny what the data indicates.

Tomenable
09-09-16, 19:48
Ok. We can merge my thread into that one started by Angela. She was first. :smile:

MarkoZ
09-09-16, 20:16
MarkoZ,



It was, and still is, feasible. Angela is right.

The fact that 2 out of 3 branches of L23 are found in Yamnaya - both Z2103 and newly discovered GG400 - makes it even more probable that L51 was also present in some of Yamnaya sub-groups. This paper actually strengthens the case for "L51 out of Yamnaya".

How do you imagine L51 emerging from L23 in Iberia, when both Z2103 and GG400 emerged from L23 in Russia?

Remember that not much time separates these clades. All of that "children-making" was within several centuries.

The trifurcation of L23 into L51, Z2103 and GG400 most probably took place within the Yamnaya culture.

I used to be against this idea too, but one cannot deny what the data indicates.

You just explained what you believe to be the case in the absence of data and went on to say that criticism of your proposed model necessarily rests on a denial of the data. This is remarkable mental gymnastics.

Anyway, the immediate ancestor of R1b1a2* in the central Balkans wasn't found in the northern Pontic, so this model necessarily requires an earlier migration.

holderlin
10-09-16, 19:01
A linear descent of European R1b from Yamnaya was never feasible, hence the ad hoc hypothesis of continuous incursions from the Eastern European grasslands into the central Balkans for which there is no archeological evidence.

There is a ton of evidence for steppe into the Balkans.

It's in Western Europe and NW Europe where steppe incursion is harder to prove archaeologically.

holderlin
10-09-16, 19:25
This is supportive of a steppe origin because it only gives higher resolution to the tree. What it's not in support of is that Yamnaya males from the latter period are ancestral to European L51.

I believe this is in support of an earlier, or at the very least "separate" departure into Europe independent of Yamnaya horizon male lines. An earlier departure is supported by the linguistics. This branch would be the ancestors of Celto-Italic and likely Tocharian speakers as well. Tocharian just went the other direction. These languages retain very archaic forms of IE and show remarkable similarities to the most archaic IE being Hittite.