Polymorphism study of BMP-15 (FecXR) and GDF-9 gene related with twinning in cattle

Abstract

Natural mutations in prolificacy genes in some species especially sheep has been shown transforming growth factor beta (TGF-β) super family ligands such as growth differentiation factor 9 (GDF9), bone morphogenetic protein 15 (BMP15) and their type I receptor (bone morphogenetic protein receptor, BMPR1B) crucial for ovulation and as well as for increasing litter size. Mutations in any of these genes increased prolificacy in carrier. The present investigation was carried out for identification of fecundity genes in cattle, with comparison of DNA fragment between dams bearing twin and singleton and to see inheritance pattern of these fragments in their twin progenies. The animals belonged to six breeds viz. pure (Sahiwal and Hariana) and three crossbreeds (Karan Swiss, Karan Fires, Holstein Friesian) besides other cross breeds of unknown lineage selected from field. The study involved analysis of genome related to twinning using molecular markers (PCR) on BMP-15 (FecXR) gene and A competitive technique called tetra-primer amplification refractory mutation system-PCR was adapted to type G1 locus mutation GDF-9 fecundity gene. PCR analysis of the FecXR allele of the BMP-15 gene detected the presence of wild-type allele in the dams and their progenies. An allele specific primer used for detection of GDF-9 gene mutation, identified only wild-type and control fragment which revealed the absence of the mutant fragment for this gene locus. The study revealed monomorphic pattern of the two fecundity genes BMP-15 and GDF-9 genes, which has no effect on twinning in cattle.