Novel single nucleotide polymorphisms of GnRHR gene and their association with litter size in goats
Abstract. In the present study, the polymorphisms of gonadotropin-releasing hormone receptor (GnRHR) gene were analysed as a genetic marker candidate for litter size in 720 individuals from Shaanan goats (SG) and Boer goats (BG). Two alleles (A and C), two observed genotypes (AA and AC), and single nucleotide polymorphisms (SNPs) were detected. The frequencies of alleles A and C in two goat breeds were 0.78–0.82 and 0.18–0.22, respectively. The SNP locus was in Hardy–Weinberg disequilibrium in two goat breeds (P<0.05). In addition, comparisons between the nucleotide sequences of AA and AC genotypes showed one mutation (T>A) at exon 2. The results showed that AA genotype was associated with better litter size in SG and BG breeds. Therefore, these results suggest that GnRHR gene is a strong candidate gene that affects litter size in goats.