Genetic characterization of some Turkish sheep breeds based on the sequencing of the Ovar-DRB1 gene in the major histocompatibility complex (MHC) gene region

Abstract

In this research, Ovar-DRB1 gene in the major histocompatibility complex (MHC) gene region was surveyed by DNA sequencing in some of the native sheep breeds that are reared in Turkey. A total of 80 samples were collected from eight different Turkish native sheep breeds, and these samples were used for DNA sequencing. The exon 2 region of Ovar-DRB1 in the MHC gene region was polymerase chain reaction (PCR) amplified and sequenced. A total of 25 new alleles were revealed in the Ovar-DRB1 gene in Turkish native sheep breeds with 24 variable sites; only 13 sites were parsimony informative. The average pairwise genetic distance was 0.029 % for the Ovar-DRBI gene exon 2 region. The sequence variations at eight different positions (7026, 7036, 7040, 7053, 7059, 7069, 7131 and 7214) are found in all of the studied samples. G -> C transversion at position 7081 is only seen in Akkaraman sheep breed, whereas T -> C transition at position 7097 is only seen in one sample from the Akkaraman breed. Overall, two main groups were detected among the 25 alleles from Turkish native sheep breeds. All Daglic and Kivircik alleles and one allele from Karayaka, Malya and Sakiz are grouped together while all the other breeds are grouped in the other branch.