Y-chromosome diversity in modern Bulgarians: new clues about their ancestry

PLoS One. 2013;8(3):e56779. doi: 10.1371/journal.pone.0056779. Epub 2013 Mar 6.

Abstract

To better define the structure and origin of the Bulgarian paternal gene pool, we have examined the Y-chromosome variation in 808 Bulgarian males. The analysis was performed by high-resolution genotyping of biallelic markers and by analyzing the STR variation within the most informative haplogroups. We found that the Y-chromosome gene pool in modern Bulgarians is primarily represented by Western Eurasian haplogroups with ∼ 40% belonging to haplogroups E-V13 and I-M423, and 20% to R-M17. Haplogroups common in the Middle East (J and G) and in South Western Asia (R-L23*) occur at frequencies of 19% and 5%, respectively. Haplogroups C, N and Q, distinctive for Altaic and Central Asian Turkic-speaking populations, occur at the negligible frequency of only 1.5%. Principal Component analyses group Bulgarians with European populations, apart from Central Asian Turkic-speaking groups and South Western Asia populations. Within the country, the genetic variation is structured in Western, Central and Eastern Bulgaria indicating that the Balkan Mountains have been permeable to human movements. The lineage analysis provided the following interesting results: (i) R-L23* is present in Eastern Bulgaria since the post glacial period; (ii) haplogroup E-V13 has a Mesolithic age in Bulgaria from where it expanded after the arrival of farming; (iii) haplogroup J-M241 probably reflects the Neolithic westward expansion of farmers from the earliest sites along the Black Sea. On the whole, in light of the most recent historical studies, which indicate a substantial proto-Bulgarian input to the contemporary Bulgarian people, our data suggest that a common paternal ancestry between the proto-Bulgarians and the Altaic and Central Asian Turkic-speaking populations either did not exist or was negligible.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bulgaria
  • Chromosomes, Human, Y / genetics*
  • Genealogy and Heraldry*
  • Genetic Variation*
  • Geography
  • Haplotypes / genetics
  • Humans
  • Male
  • Microsatellite Repeats / genetics
  • Phylogeny
  • Principal Component Analysis

Grants and funding

This study was supported by the National Science Fund of Bulgaria, project “Characterization of the anthropo-genetic identity of Bulgarians”, contract number DOO 2-110/22.05.2009, and Fondazione Alma Mater Ticinensis (to OS and AT), the Italian Ministry of the University: Progetti Ricerca Interesse Nazionale 2009 (to OS and AT). NA-Z was supported by a fellowship from the Institute of International Education. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.