Genetic Heritage of the Balto-Slavic Speaking Populations: A Synthesis of Autosomal, Mitochondrial and Y-Chromosomal Data

TLDR

The Slavic branch of the Balto‑Slavic sub‑family diverged rapidly during early medieval expansion from Central‑East Europe, incorporating genetic components from numerous autochthonous populations into its gene pools. This study aims to characterize genetic variation in all extant Balto‑Slavic speaking ethnic groups by analyzing mitochondrial DNA, Y‑chromosomes, and genome‑wide SNPs, while also reassessing the Slavic phylogeny within the Balto‑Slavic branch. The authors examined 6,876 mtDNA sequences, 6,079 Y‑chromosome haplotypes, and 296 genome‑wide SNP profiles from Balto‑Slavic populations and compared them to other European groups. Genetic distances among Balto‑Slavic populations based on autosomal and Y‑chromosomal loci show a 0.9 correlation with each other and geography, a 0.7 correlation with mitochondrial DNA and linguistic affiliation, and reveal two substrata—central‑east European for West and East Slavs, and south‑east European for South Slavs—along with shared ancestry or modest gene flow inferred from identical‑by‑descent segments.

Abstract

The Slavic branch of the Balto-Slavic sub-family of Indo-European languages underwent rapid divergence as a result of the spatial expansion of its speakers from Central-East Europe, in early medieval times. This expansion–mainly to East Europe and the northern Balkans–resulted in the incorporation of genetic components from numerous autochthonous populations into the Slavic gene pools. Here, we characterize genetic variation in all extant ethnic groups speaking Balto-Slavic languages by analyzing mitochondrial DNA (n = 6,876), Y-chromosomes (n = 6,079) and genome-wide SNP profiles (n = 296), within the context of other European populations. We also reassess the phylogeny of Slavic languages within the Balto-Slavic branch of Indo-European. We find that genetic distances among Balto-Slavic populations, based on autosomal and Y-chromosomal loci, show a high correlation (0.9) both with each other and with geography, but a slightly lower correlation (0.7) with mitochondrial DNA and linguistic affiliation. The data suggest that genetic diversity of the present-day Slavs was predominantly shaped in situ, and we detect two different substrata: 'central-east European' for West and East Slavs, and 'south-east European' for South Slavs. A pattern of distribution of segments identical by descent between groups of East-West and South Slavs suggests shared ancestry or a modest gene flow between those two groups, which might derive from the historic spread of Slavic people.