Genomic characterization of the Przewalski's horse inhabiting Mongolian steppe by whole genome re-sequencing

The Przewalski's horse is a rare and endangered species and the last existing wild horses. Therefore, its genetic characterization is important to facilitate the systematic preservation and promotion of its gene pool. Karyotypes of chromosomes confirmed that the two tested horses were indeed Przewalski's horses (2n=66). Their genome was characterized using whole-genome re-sequencing and a comprehensive list of genetic variants including SNPs and INDELs was developed. We found a total number of 5,879,868 SNPs in the male and 6,040,778 SNPs in the female. Homozygous variations were more abundant than heterozygous variations, probably caused by inbreeding during the restoration process of species from only 13 horses. In conclusion, our results provide valuable information such as additional sequence information for equine researchers and can help to figure out how the horse genome was changed by domestication in recent years.