Detection of the effect of the KISS1 gene on reproductive parameters in Saanen goats

Abstract

The KISS1 gene, which activates G protein-coupled receptor-54 (GPR54) and plays a crucial role in the neuroendocrine regulation of GnRH secretion, is known to encode a family of neuropeptides called kisspeptins. Therefore, the KISS1 gene is thought to be associated with sexual maturity, offspring development, and estrus. The g.2124T>A polymorphism of the KISS1 gene, is believed to affect the reproductive system, has been studied in Indonesian goat breeds, Damascus, Zarabi, Baladi, Gaddi, Kaligesing, Guanzong, Xinong Saanen and Boer goat breeds until now. These studies are generally related determining polymorphism frequencies or the effect of genotype on litter size. The study aims to determine the allele and genotype frequencies of the KISS1 gene g.2124T>A SNP by the PCR-RFLP method and define the relationship between the genotypic structures and reproductive parameters such as luteal growth, maximum corpus luteum diameter, and mating rate in Saanen goats (n=30). According to the results, the genotype frequencies in Saanen goats for the KISS1 gene g.2124T>A were 10.35%, 55.17%, and 34.48% for AA, TT and AT, respectively. Moreover, the genotypic structure did not have a statistically significant effect on the investigated fertility characteristics. The average values of expected heterozygosity (He), observed heterozygosity (Ho), the effective number of alleles (Ne), fixation index values (FIS), and the polymorphism information content (PIC) were 0.3996, 0.3448, 1.6655, 0.8629 and 0.855, respectively. The Hardy-Weinberg chi-square (χ2) value was found to be 0.5435. In conclusion, it was found necessary to study the KISS1 - g.2124T>A polymorphism in larger herds with different gene pools as a reason for the existence of genotypic variation and the narrow population size.