Some mutations in Bone Morphogenetic Protein 15 (BMP15) gene have been known to be associated with prolificacy in various breeds of sheep. Polymorphism of BMP15 gene exon 2 was studied in 100 Mehraban and 100 Lori ewes, using PCR-SSCP and DNA sequencing methods. A new point mutation (G→A) was found at position 57 of the amplified 312-b fragment of BMP 15 gene exon 2. The frequencies of the AG and GG genotypes were 69.4% and 30.6% in Mehraban and 44.7% and 55.3% in Lori ewes, respectively. No individual carrying the AA genotype was found in the studied population. The allelic frequencies for A and G alleles were 34.7% and 65.3% in Mehraban and 22.4% and 77.6% in Lori ewes, respectively. Average litter size in the AG genotype (1.56) was significantly (P < 0.01) higher than the GG ewes (1.08). The results of the present study indicated the potential of the observed SNP in exon 2 of BMP15 for further exploitation in marker assisted selection to improve reproduction efficiency of Mehraban and Lori sheep.
