Genetic diversity assessment for reintroduced Przewalski’s horse (Equus ferus) based on newly developed SSR markers

Abstract

Przewalski’s horse (Equus ferus) is a national protected species in China. It first became extinct in the wild in 1976, and was reintroduced to the Kalamaili National Park (KNP) in Xinjiang, China in 2001. This study aimed to analyze the genetic diversity and structure of the reintroduced population of Przewalski’s horse in KNP. Here, we developed and designed microsatellite molecular markers using 48 feces samples and combined this with published genomic data from the species. A preliminary analysis of genetic diversity within the Przewalski’s horse population in the KNP was conducted using 16 pairs of simple sequence repeat (SSR) markers with high levels of polymorphism and high stability. A total of 199 alleles were amplified using 16 SSR primer pairs, averaging 12.438 at each locus. In the sample of 48 genomes, the average effective number of alleles detected was 2.695, the average expected heterozygosity was 0.577 and the inbreeding coefficient was 0.232. Twelve loci showed significant deviation from Hardy–Weinberg equilibrium following Bonferroni sequential corrections. Our research finds that the genetic diversity of the Przewalski’s horse population in the KNP remains high. This is the first research using newly developed SSR markers to describe the genetic diversity and structure of the reintroduced Przewalski’s horse population in KNP, China. As such, it can inform future reintroductions of the species and conservation measures.