Polymorphism of fecundity genes, BMPR1B, BMP15 and GDF9, in tropical goat breeds of Kerala

Abstract

Goat rearing practices in Kerala is mainly centred on two of its native goat breeds, Attappady Black and Malabari. Malabari goats are highly prolific and commonly give birth to two to four kids per kidding, while Attappady Black breed is less prolific; they produce only one or hardly two kids per kidding and multiple ovulation is very rare or nil. Eleven point mutations in the three prolificacy genes, BMPR1B, GDF9 and BMP15, have been identified for making changes in the prolificacy rate of sheep by affecting follicular development and ovulation rate. During the course of this study, we aimed to find out whether any of these gene mutations were responsible for prolificacy difference in Attappady Black and Malabari goats. Test animal selection was done based on their prolificacy rate. Blood samples from individual animals were collected; genomic DNA was extracted and SNP specific Tetra- Primer- ARMS PCR and touch down PCR amplifications were performed to detect any specific mutation in the target genes. All the tested animals, irrespective of breeds were found to carry the heterozygous genotype ‘AG’ for the BMPR1B gene. In the case of BMP15 and GDF9, none of the specific mutations were detected and all the animals were carrying only the wild genotype. Heterozygous genotype for BMPR1B, sheep fecundity gene mutation, appeared to have no significant effect on prolificacy rate as the same genotype was found in both the lowly and highly prolific breeds, Attappady Black and Malabari.