Study On Candidate Gene Related To Breeding Performance Of Goats In Southwest Of China

Goat breeds resources with significant economic value were rich in southwestChina. This study used assisted selection with molecular marker and based ontraditional breeding method, which had some inadequacies yet. PRND、MAPK3、NPYand NPY-Y1R gene was chosen in this present study as candidate gene. The objectiveswere to identify the polymorphism of NPY-Y1R gene and its association withreproductive traits and to provide a scientific basis for marker-assisted selection for highprolificacy in10goat breeds from southwest of china.According to the sequence of mRNA of Ovis aries PRND gene and DNA sequenceof Bos Taurus PRND gene, six pairs of primers were designed to characterize PRNDgene SNP in nine China’s breeds of goat and Boer. In addition, it determined thepossibility between the polymorphisms and the female goat fertility. Eight nucleotidepositions showed variation: T28C, A151G, G793A, C806T, G874C, T894C, T940G, andG944A. Six polymorphisms following: the mutations of G793A, C806T, G874C,T894C, T940G, and G944A were in3’ flaking region. T28C was a silent mutation, andA151G determined a T51A amino acid change. Otherwise, the mutations of T28C andA151G were completely linked. Moreover, the associations between thesepolymorphisms and reproduction traits were analyzed in Gulin Ma, Chuangdong Whiteand Guizhou White goats. Nevertheless, in three breeds of goats, the Litter size andbirth weight were no significant differences by PRND genotype, but the former wassignificantly influenced by sire, kidding season, parity.According to the sequence of Bos Taurus NPY-Y1R gene, four pairs ofprimers(P1~P4) were designed to characterize NPY-Y1R gene SNP in nine China’sbreeds of goat and Boer by SSCP. Only the amplified products of primer P4displayedpolymorphisms. For primer P4, four genotypes (AA, AB, BB and AC) were detected intotal ten goat breeds, but the genotype CC was not found. The sequencing resultsshowed that the allele B compared to A had one point mutation of C to T in the locus6174, and the allele C compared to A also had one point mutation of C to T in the locus6189. The goats with genotype AB have significant higher litter size than those withgenotype AA in Guizhou white and Chuandong White goat(P<0.05), and the birthweight with genotype AA and BB had no significant difference in three breeds of gostsof Gulin Ma, Guizhou white and Chuandong White (P>0.05). The results preliminarily indicated that the NPY-Y1R gene may be a major gene, and the single base mutation ofC6174T may be treated as molecular marker for choosing litter size in goats.There were no polymorphisms in the amplification regions of MAPK3and NPYgene in ten goat breeds. The results indicated that the region of BMP2gene may not bethe functional domains that affect the high prolificacy in goats.