The Association Analysis Between the SNPs of Leptin Gene and Litter Size Trait in Pigs

The research was aimed to analyze the association of Leptingene and breed traits on pigs. Three pairs of primers were designed which based on DNA sequence of pig Leptin gene (GenBank accession No.U66254, AF026976),the single nucleotide polymorphisms (SNPs) of Leptin gene were detected by PCR-SSCP in Sujiang and Jiangquhai pigs. The results showed that three genotypes of AA,AB and BB were identified, and the mutation (T3469C) in CDS of Leptin gene was found,but amino acid change weren't happened. The Chi-square test results showed that the Leptin genotype distribution of Sujiang and Jiangquhai pigs was in Hardy-Weinberg equilibrium (P>0.05). The polymorphism information content (PIC) were moderate polymorphism in Sujiang pigs,and low polymorphism in Jiangquhai pigs. The statistic analysis results showed that there were no significant association between the SNP of Leptin genotype and litter size trait(P>0.05). But the average litter size of T3469C site AB genotype was higher than AA and BB genotypes, it was concluded that the T3469C polymorphism of Leptingene might be the genetic marker which potentially affected pig breed traits.