Relationship Of SNP Of GnIH With Prolific Performence Of Goats

Looking for molecular markers tightly linked with prolific trait in DNA level, researching the function of excellent genes and making organic combination of modern molecular breeding techniques with conventional breeding techniques are the trend of development of goat breeding. In the study,380goats which comprised of two breeds Xinong Sannen dairy goat and Boer goat were selected and the key function gene was gonadotropin-inhibitory hormone(GnIH). This study investigated the polymorphisms GnIH genes in Xinong Saanen (SN) and Boer (BG) goat breeds by DNA sequencing and PCR-RFLP and analyzed the association of single nucleotide polymorphisms (SNPs) with litter size. the characteristics of amino acid sequences were analyzed using bioinformatics. Finally, the research analyzed the pyramiding effect of GnIH genes on litter size. The main results were as follows:1、GnIH gene was studied as a candidate gene for the prolificacy of xinong Saanen Dairy Goat and Boer Goat. Seven pairs of primers were designed to detect single nucleotide polymorphisms, three SNPs were detected in GnIH gene(g.265C>G, g.1987G>A, g.3665C>T).2、The g.265C>G SNP was in intron1. Three genotypes(CC、CG and GG) were detected both in xinong Saanen Dairy and Boer Goat. In SN goats, the result showed that the individuals with CC combination genotype had higher litter size than those CG and GG in the average parity (P<0.05). In the first, the individuals with CG combination genotype did not have higher litter size than those with GG(P>0.05), while in the other and average parity, the individuals with CG combination genotype had higher litter size than those with GG(P<0.05). In BG goats, the individuals with GG combination genotype had higher litter size than those with CG and CC in the first(P<0.05), while in the second and third, the individuals with CG combination genotype had higher litter size than those with GG and CC(P<0.05).3、The position of g.1987G>A SNP was in exon2, Three genotypes(CC、CG and GG) were detected but there did not exist pertinence between the genotype and litter size(P>0.05). 4, The g.3665C>T SNP was in intron1, two genotypes(TC and TT) were detected both in xinong Saanen Dairy and Boer Goat. In BG goats, the result showed that the individuals with TT combination genotype have higher litter size than those with TC in the third and fourth (P<0.05).