Study on genetic variability in MHC-DRB1 second exon in Makuie sheep breed population

In the present study polymorphism of the exon 2 of MHC (Major Histocompatibility Complex) gene in Makuie sheep breed was studied. Genomic DNA from blood samples of 90 sheep was extracted and a 279 bp MHC exon 2 fragment was amplified using polymerase chain reaction (PCR). PCR products were subjected to enzymatic digestion using RsaI endonuclease. Digested PCR products were electrophoresed on 2% agarose gel. The results showed the existence of 10 alleles: A, B, E, F, I, M, O, P, Q and V for the exon 2 of the MHC gene, with the frequencies of 0.4756, 0.0976, 0.0183, 0.0366, 0.0549, 0.0122, 0.1098, 0.0915, 0.0854 and 0.0183, respectively. Eighteen genotypes: AA, AB, AE, FF, AM, BO, EO, IO, OM, AP, BP, OP, PP, AQ, OQ, PQ, QQ and AV with the frequencies of 0.317, 0.1585, 0.0121, 0.0365, 0.0121, 0.0243, 0.0243, 0.1097, 0.0121, 0.0487, 0.0121, 0.0365, 0.0365, 0.0487, 0.0121, 0.0121, 0.0487 and 0.0365, respectively were identified in the population under study. Effective number of alleles and heterozygosity for the examined region were 3.7231 and 0.7314, respectively. Chi-square test showed that the examined sheep population was not in Hardy-Weinberg equilibrium in the examined region