Genomic history of Northern Eurasians includes East-West and North-South gradients

russia-uralic-ibd

Open Access article on modern populations (including ancient samples), Between Lake Baikal and the Baltic Sea: genomic history of the gateway to Europe, by Triska et al., BMC Genetics 18(Suppl 1):110, 2017.

Abstract:

Background
The history of human populations occupying the plains and mountain ridges separating Europe from Asia has been eventful, as these natural obstacles were crossed westward by multiple waves of Turkic and Uralic-speaking migrants as well as eastward by Europeans. Unfortunately, the material records of history of this region are not dense enough to reconstruct details of population history. These considerations stimulate growing interest to obtain a genetic picture of the demographic history of migrations and admixture in Northern Eurasia.

Results
We genotyped and analyzed 1076 individuals from 30 populations with geographical coverage spanning from Baltic Sea to Baikal Lake. Our dense sampling allowed us to describe in detail the population structure, provide insight into genomic history of numerous European and Asian populations, and significantly increase quantity of genetic data available for modern populations in region of North Eurasia. Our study doubles the amount of genome-wide profiles available for this region.

We detected unusually high amount of shared identical-by-descent (IBD) genomic segments between several Siberian populations, such as Khanty and Ket, providing evidence of genetic relatedness across vast geographic distances and between speakers of different language families. Additionally, we observed excessive IBD sharing between Khanty and Bashkir, a group of Turkic speakers from Southern Urals region. While adding some weight to the “Finno-Ugric” origin of Bashkir, our studies highlighted that the Bashkir genepool lacks the main “core”, being a multi-layered amalgamation of Turkic, Ugric, Finnish and Indo-European contributions, which points at intricacy of genetic interface between Turkic and Uralic populations. Comparison of the genetic structure of Siberian ethnicities and the geography of the region they inhabit point at existence of the “Great Siberian Vortex” directing genetic exchanges in populations across the Siberian part of Asia.

EEHG-CHG-Neolithic_Farmer-ANE
f3 values to estimate (a) Eastern European Hunter-Gatherer, b Neolithic Farmer, c Caucasus hunter-gatherer, and d) Mal’ta (Ancient North Eurasian) ancestry in modern humans

Slavic speakers of Eastern Europe are, in general, very similar in their genetic composition. Ukrainians, Belarusians and Russians have almost identical proportions of Caucasus and Northern European components and have virtually no Asian influence. We capitalized on wide geographic span of our sampling to address intriguing question about the place of origin of Russian Starovers, an enigmatic Eastern Orthodox Old Believers religious group relocated to Siberia in seventeenth century. A comparative reAdmix analysis, complemented by IBD sharing, placed their roots in the region of the Northern European Plain, occupied by North Russians and Finno-Ugric Komi and Karelian people. Russians from Novosibirsk and Russian Starover exhibit ancestral proportions close to that of European Eastern Slavs, however, they also include between five to 10 % of Central Siberian ancestry, not present at this level in their European counterparts.

russian-uralic-turkicadmixture
Admixture proportions in studied populations, K = 6. Populations from the Extended dataset. Abbreviated population codes: NSK – Russians from Novosibirsk; STV -Starover Russians; ARK: Bashkirs from Arkhangelskiy district; BRZ – Bashkirs from Burzyansky district

Conclusions
Our project has patched the hole in the genetic map of Eurasia: we demonstrated complexity of genetic structure of Northern Eurasians, existence of East-West and North-South genetic gradients, and assessed different inputs of ancient populations into modern populations.

Featured image, from the article: “Departures from the expected IBD. Shown populations exceed the expected IBD sharing by more than two standard deviations.”

Related:

More evidence on the recent arrival of haplogroup N and gradual replacement of R1a lineages in North-Eastern Europe

sejma-turbino-phenomenon

A new article (in Russian), Kinship Analysis of Human Remains from the Sargat Mounds, Baraba forest-steppe, Western Siberia, by Pilipenko et al. Археология, этнография и антропология Евразии Том 45 № 4 2017, downloadable at ResearchGate.

Abstract:

We present the results of a paleogenetic analysis of nine individuals from two Early Iron Age mounds in the Baraba forest -teppe, associated with the Sargat culture (fi ve from Pogorelka-2 mound 8, and four from Vengerovo-6 mound 1). Four systems of genetic markers were analyzed: mitochondrial DNA, the polymorphic part of the amelogenin gene, autosomal STR-loci, and those of the Y-chromosome. Complete or partial data, obtained for eight of the nine individuals, were subjected to kinship analysis. No direct relatives of the “parent-child” type were detected. However, the data indicate close paternal and maternal kinship among certain individuals. This was evidently one of the reasons why certain individuals were buried under a single mound. Paternal kinship appears to have been of greater importance. The diversity of mtDNA and Y-chromosome lineages among individuals from one and the same mound suggests that kinship was not the only motive behind burying the deceased people jointly. The presence of very similar, though not identical, variants of the Y chromosome in different burial grounds may indicate the existence of groups such as clans, consisting of paternally related males. Our conclusions need further confi rmation and detailed elaboration. Keywords: Paleogenetics, ancient DNA, kinship analysis, mitochondrial DNA, uniparental genetic markers, STR-loci, Y-chromosome, Baraba forest-steppe, Sargat culture, Early Iron Age.

Baraba-West-Siberian-Plain-Eurasia
From the older study of the same region (Baraba, numbered 4) “Location of ancient human groups with a high frequency of mtDNA haplogroups U5, U4 and U2e lineages. The area of Northern Eurasian anthropological formation is marked by yellow region on the map (References: 1. Bramanti et al., 2009; 2. Malmstrom et
al., 2009; 3. Krause et al., 2010; 4. this study)”

baraba-cultures-chronology
Chronological time scale of Bronze Age Cultures from the Baraba region
This is the same team that brought an ancient mtDNA study of different cultures within the Baraba steppe-forest region (from the Open Access book Population Dynamics in Prehistory and Early History).

The Baraba steppe-forest is a region between the Ob and Irtysh rivers (about 800 km from west to east), stretching over 200 km from the taiga zone in the north to the steppes in the south.

The new study brings a more recent picture of the region, from the Iron Age Sargat culture, ca. 500 BC – 500 AD, with five samples of haplogroup N and two samples of haplogroup R1a.

R1a lineages in the region probably derive from the previous expansion of Andronovo and related cultures, which had absorbed North Caspian steppe populations and their Late Indo-European culture.

N subclades prevalent in certain modern Eurasian populations are probably derived from the expansion of the Seima-Turbino phenomenon.

While samples are scarce, Y-DNA data keeps showing the same picture I have spoken about more than once:

N subclades (potentially originally speaking Proto-Yukaghir languages) gradually replacing haplogroup R1a (originally probably speaking Uralic languages), probably through successive founder effects (such as the bottlenecks found in Finland), which left their Uralic culture and ethnolinguistic identification intact.

Therefore, late Corded Ware groups of North-Eastern Europe (in the Forest Zone and the Baltic), mainly of R1a-Z645 subclades, probably never adopted Late Indo-European languages.

Related:

Indo-European demic diffusion model, 3rd edition

pca-yamna-corded-ware

I have just uploaded the working draft of the third version of the Indo-European demic diffusion model. Unlike the previous two versions, which were published as essays (fully developed papers), this new version adds more information on human admixture, and probably needs important corrections before a definitive edition can be published.

The third version is available right now on ResearchGate and Academia.edu. I will post the PDF at Academia Prisca, as soon as possible:

pca-map-yamna-corded-ware-bell-beaker
Map overlaid by PCA including Yamna, Corded Ware, Bell Beaker, and other samples

Feel free to comment on the paper here, or (preferably) in our forum.

A working version (needing some corrections) divided by sections, illustrated with up-to-date, high resolution maps, can be found (as always) at the official collaborative Wiki website indo-european.info.