Genetic and phylogenetic analysis of mitochondrial D-loop HVR I region in three breeds of native sheep Iran (Taleshi, Shal and Makui)

The genetic purity of sheep breeds is declining due to uncontrolled crossbreeding, so it is essential to preserve biodiversity in native breeds as a national asset. Therefore, the purpose of this study was to investigate the genetic and phylogenetic diversity of the mitochondrial HVR I region between the three Taleshi, Makui and Shal breeds. For this purpose, HVR I sequences of these three breeds were downloaded from NCBI database. Nucleotide diversity for Taleshi, Shawl and Makui breeds calculated 0.0416, 0.04552 and 0.04422, respectively, and haplotype diversity in all three breeds was estimated to be 1.00. In addition, the results of molecular analysis of variance (AMOVA) showed that the diversity within populations was about %100 and in fact the total diversity was included and the diversity between populations was %0. These results indicated high genetic variation in three sheep breeds. Negative Tajima''s D for Taleshi breed indicated that the this population is expanding after going through a recent bottleneck and selection sweep is in progress, while positive Tajima''s D for shawl and Makui breeds demonstrated that these two populations are balancing selection. The NJ phylogenetic test results indicated that all three breeds of sheep were classified into haplotype D. From the classification of these breeds with the Caucasian and Turkish breeds in one branch, it can be concluded that these three breeds are the ancient breeds of sheep and more efforts should be made to preserve these national assets.