Npy Gene Single Nucleotide Polymorphisms And Population Genetics Analysis In The Hu Sheep

In the current study, the NPY gene of Hu sheep was cloned by Bioinformatics method and the gene polymorphism was detected by PCR-SSCP method. According to population genetics analysis for NPY gene single nucleotide polymorphism and the association analysis between NPY gene polymorphism and early growth traits in Hu sheep, the possibility that NPY SNPs as early growth traits of molecular markers in Hu sheep was discussed, it could be used to provide the basis for molecular marker-assisted breeding in Hu sheep.1. Cloning and Bioinformatics analysis of NPY gene of Hu sheepAfter multiple sequence alignment of NPY DNA sequences, According to conserved regions, three pairs of primers of NPY gene were designed to clone NPY gene of Hu sheep. NPY gene of Hu sheep was cloned, its DNA is6721bps in length which codes97amino acids. The molecular weight of NPY protein in Hu sheep was1.07182KDa and its isoelectric point was7.88. The results showed that ovis aries were more closely related to Hu sheep than others, followed by Bos Taurus97.94%, Macaca mulatta94.85%, Equus caballus93.81%, Homo sapiens92.78%, canis_familiaris92.78%, Pan troglodytes91.75%and Mus musculus88.66%. The putative NPY protein of Hu sheep contains many fuctional site and motif. The result revealed that this protein had conserved structure with other NPY.2. NPY PCR-SSCP detection of single nucleotide polymorphism and analysis of population genetics in the Hu sheepIn this study, by PCR-SSCP method, SNPs of the whole cloned NPY gene was detected in Hu sheep. Four SNPs were found in the Amplified fragments of N10、N17、N20and N21among twenty-three primers. Allele A majored in all of the mutations in the Hu sheep group. Among the four SNPs, SNPn10and SNPn17behaved3genotypes while SNPn20and SNPn21behaved2genotypes. Except for the insertion or deletion mutation in SNPnio, all polymorphic loci were in Hardy-Weinberg equilibrium (P>0.05) of Hu sheep group. SNPn17polymorphic information content was0.2909belonging to moderate polymorphism.The gene frequencies and genotype frequencies χ2test results between meat line and general line showed that there were significant differences (P <0.01) in SNPnio, SNPn17genotype frequencies, imultaneously, SNPnio (deletion)、of meat line group、SNPn17of general line group were not in Hardy-Weinberg equilibrium (P <0.01).Gene effect analysis reveal that the homozygous mutant-type and hybrid type have increased weaning weight trend. The SNPN10(deletion) was significantly correlated with daily gain (P <0.05) by the correlation and partial correlation analysis for birth weight, weaning weight, and daily gain. Therefore, there may be a certain relationship between early growth traits and NPY SNPnio. Deep study can be carried out in meat line of Hu sheep at this locus, in the future.