We have analyzed mtDNA HVI sequences and Y chromosome haplogroups based on 11 binary markers in 371 individuals, from 11 populations in the Caucasus and the neighbouring countries of Turkey and Iran. Y chromosome haplogroup diversity in the Caucasus was almost as high as in Central Asia and the Near East, and significantly higher than in Europe. More than 27% of the variance in Y-haplogroups can be attributed to differences between populations, whereas mtDNA showed much lower heterogeneity between populations (less then 5%), suggesting a strong influence of patrilocal social structure. Several groups from the highland region of the Caucasus exhibited low diversity and high differentiation for either or both genetic systems, reflecting enhanced genetic drift in these small, isolated populations. Overall, the Caucasus groups showed greater similarity with West Asian than with European groups for both genetic systems, although this similarity was much more pronounced for the Y chromosome than for mtDNA, suggesting that male-mediated migrations from West Asia have influenced the genetic structure of Caucasus populations.
An older paper, but one I hadn’t taken a look at.
Unfortunately there isn’t as much detail on the mt DNA.
From one long ago read text, I can remember that one North Caucasus late neolithic site had a tendency to have Mediterranean male crania with the more robust local females. This could support that population movements into the area from the Iran/Turkey area (birthplace of the Neolithic) may have been male lead, which might give a clue as to how each the Caucasus population has such a heterogenous Y chromosome profile.