Landscape Complexity in the Caucasus Impedes Genetic Assimilation of Human Populations More Effectively than Language or Ethnicity

The analyses of 15 autosomal and 23 Y-chromosome DNA single-tandem-repeat loci in five rural populations from the Caucasus (four ethnically Georgian one Armenian) indicated that two populations, west other east Greater Mountains, were both patrilineally autosomally most differentiated each other, Georgians Armenians held an intermediate position between those two. This pattern may be due to human dispersal distinct glacial refugia last period early Holocene, followed by less gene flow among than rest Caucasus, where have undergone substantial admixture historical time. hypothesis is supported a strong correlation genetic differentiation landscape permeability migrations as determined terrain ruggedness, forest cover, snow cover. Although geographic patterns are not fully concordant, influenced show similar east-west gradient. Our results suggest this was stronger factor limiting ethnic or linguistic boundaries.