Molecular genetic assessment aids in clarifying phylogenetic status of Iranian Kerman wild sheep

Simple Summary

Asiatic mouflon (Ovis gmelini) and urial (O. vignei) are two species of wild sheep that occur throughout the mountains of Iran. At the moment, phylogenetic (“family tree”) relationships between populations of wild sheep in this region remain unclear. Three subspecies of the Asiatic mouflon and three subspecies of the urial were described in Iran. In our study, utilizing molecular genetic tools, we, for the first time, investigated the phylogenetic status of the Kerman wild sheep, as this has long been considered to be a hybrid of Asiatic mouflon and urial. We examined three specimens of Kerman sheep using nuclear and mitochondrial DNA approaches. Our results demonstrated that Kerman sheep were different from other groups and occupy an intermediate position between the two wild breeds. We demonstrated that the maternal line ancestor of the Kerman sheep belonged to the urial. In our opinion, therefore, Kerman wild sheep can be recognized as a separate subspecies of the urial.

Abstract

Two species of wild sheep inhabit Iran: Asiatic mouflon (Ovis gmelini) and urial (O. vignei). Phylogenetic relationships between populations distributed in this country are complex and still remain unclear. This study aimed to clarify, by genetic assessment, the phylogenetic status of Kerman wild sheep, considered to be a hybrid of the two species. For this purpose, we created a dataset that included specimens of O. gmelini, O. vignei, and Kerman sheep. We applied genome-wide SNP genotyping technology to analyze population structure and genetic diversity of these groups. Using Neighbor-Net and PCA plots, it was demonstrated that Kerman sheep were differentiated from other groups and occupy an intermediate position between O. gmelini and O. vignei. Using Admixture analysis, two ancestral components were identified in this population; however, admixed ancestry was not confirmed by f3 statistics. Genetic diversity in Kerman wild sheep was significantly higher than in any group of O. vignei, but lower than in O. gmelini. Additionally, we examined complete mitochondrial genomes and it was demonstrated that the matrilineal ancestor of Kerman sheep belonged to O. vignei. Our results lead to the conclusion that Kerman wild sheep can be recognized as a separate subspecies of O. vignei.