Y Chromosome Uncovers the Recent Oriental Origin of Modern Stallions

Curr Biol. 2017 Jul 10;27(13):2029-2035.e5. doi: 10.1016/j.cub.2017.05.086. Epub 2017 Jun 29.

Abstract

The Y chromosome directly reflects male genealogies, but the extremely low Y chromosome sequence diversity in horses has prevented the reconstruction of stallion genealogies [1, 2]. Here, we resolve the first Y chromosome genealogy of modern horses by screening 1.46 Mb of the male-specific region of the Y chromosome (MSY) in 52 horses from 21 breeds. Based on highly accurate pedigree data, we estimated the de novo mutation rate of the horse MSY and showed that various modern horse Y chromosome lineages split much later than the domestication of the species. Apart from few private northern European haplotypes, all modern horse breeds clustered together in a roughly 700-year-old haplogroup that was transmitted to Europe by the import of Oriental stallions. The Oriental horse group consisted of two major subclades: the Original Arabian lineage and the Turkoman horse lineage. We show that the English Thoroughbred MSY was derived from the Turkoman lineage and that English Thoroughbred sires are largely responsible for the predominance of this haplotype in modern horses.

Keywords: Equus caballus; Y chromosome; breeding; genealogy; haplotype; horse; patrilineal ancestry; phylogeny; stallion line.

MeSH terms

  • Animals
  • Europe
  • Evolution, Molecular*
  • Genetic Variation*
  • Haplotypes / genetics
  • Horses / genetics*
  • Male
  • Pedigree
  • Y Chromosome / genetics*