A new paper appeared on Current Biology, by Margaryan et al. (including Morten E. Allentoft): Eight Millennia of Matrilineal Genetic Continuity in the South Caucasus.
Among its conclusions:
The plot clearly shows the clustering of the ancient group together with the modern European, Armenian, and Caucasian populations. We observe none of the typical East Eurasian mtDNA lineages (A, C, D, F, G, and M) among the ancient individuals, and only one individual with haplogroup D is present in the modern Armenian maternal gene pool (Artsakh). As such, the archaeologically and historically attested migrations of Central Asian groups (e.g., Turks and Mongols) into the South Caucasus [14, 15] do not seem to have had a major contribution in the maternal gene pool of Armenians. Both geographic (mountainous area) and cultural (Indo-European-speaking Christians and Turkic-speaking Muslims) factors could have served as barriers for genetic contacts between Armenians and Muslim invaders in the 11th–14th centuries CE. The same pattern was observed using Y chromosome markers in geographically diverse Armenian groups.
Also, regarding the potential Indo-European migration into the area:
It appears that during the last eight millennia, there were no major genetic turnovers in the female gene pool in the South Caucasus, despite multiple well-documented cultural changes in the region [27, 28]. This is in contrast to the dramatic shifts of mtDNA lineages occurring in Central Europe during the same time period, which suggests either a different mode of cultural change in the two regions or that the genetic turnovers simply occurred later in Europe compared to the South Caucasus. More data from earlier Mesolithic cultures in the South Caucasus are needed to clarify this. During the highly dynamic Bronze Age and Iron Age periods, with the formation of complex societies and the emergence of distinctive cultures such as Kura-Araxes, Trialeti-Vanadsor, Sevan-Artsakh, Karmir-Berd, Karmir-Vank, Lchashen-Metsamor, and Urartian, we cannot document any changes in the female gene pool. This supports a cultural diffusion model in the South Caucasus, unless the demographic changes were heavily male biased, as was most likely the case in Europe during the Bronze Age migrations [29, 30]. However, genome-wide data from the few Bronze Age individuals published so far from the South Caucasus also support a continuity scenario . Another possibility is that any gene flow into the South Caucasus occurred from groups with a very similar genetic composition, facilitating only subtle genetic changes that are not detectable with the current datasets.
I would obviously support the latter possibility, a demic diffusion that can be shown by precise subclade and admixture analyses, because cultural diffusion is quite difficult to justify in any ancient setting. Since it is most likely south-eastern European R1b-Z2103 lineages (or R1b-M269, if resurged during the proto-language transition in the Balkans) the original marker of Palaeo-Balkan speakers, that is what one should be looking for in Y-DNA investigation in the area. Since migrations were probably male-biased, it is not likely that mtDNA was much affected. But, especially during the Iron Age, a change should also be seen, marked by the appearance of (recent) U subclades.
News of the article seen first in Eurogenes (you can see the specific samples there).
Featured image is from the article.