Two novel SNPs of the type I gonadotropin releasing hormone receptor gene and their associations with superovulation traits in Chinese Holstein cows

The present study attempts to explore a predictor to forecast superovulation response on the basis of associations between superovulation performance and gene polymorphism, variation in the bovine type I gonadotropin releasing hormone receptor (GnRHRI) gene was investigated using PCR-single-strand conformational (PCR-SSCP) and DNA sequencing. Two single nucleotide polymorphisms (SNPs) of G286A and T340C were found in exon I of the bovine GnRHRI gene and evaluated its associations with superovulatory response in 104 Chinese Holstein cows. In polymorphic locus 286, all cows without superovulation response were mutations with genotype of GG. Individuals with GA genotype had a significant increase in total number of ova (TNO) (P < 0.01), and produced more transferable embryos (NTE) than those with GG genotype (P < 0.05). These results indicate that GnRHRI gene is a potential marker for superovulation response and can be used to predict the superovulatory response in Chinese Holstein cows.