柯乐猪CRISP 3基因SNP鉴定及其对繁殖性状的影响

CRISP3 gene SNP identification and its impact on reproductive traits in Kela pigs

为分析富半胱氨酸的分泌蛋白3(cysteine rich secretory protein 3,CRISP3)基因单核苷酸多态性(single nucleotide polymorphism,SNP)位点对柯乐猪繁殖性状的影响,采用Sanger测序法检测250头健康经产柯乐猪母猪CRISP 3基因的SNP突变位点,利用SPSS 22.0软件分析SNP位点与柯乐猪产活仔猪数、初生窝重、初生均重、断奶窝重、断奶仔猪数和断奶均重6个指标的关联性。结果显示,在柯乐猪CRISP 3基因第4内含子共发现3个SNP突变位点,即g.43796318T>C、g.43796424T>A和g.43796425G>T,均存在3种基因型。g.43796318T>C和g.43796424T>A位点的优势基因型为TT,优势等位基因为T;g.43796425G>T位点的优势基因型为GG,优势等位基因为G。χ^(2)检验显示,g.43796318T>C位点基因型分布符合Hardy-Weinberg平衡状态(P>0.05);g.43796424T>A和g.43796425G>T位点基因型分布均极显著(P<0.01)偏离Hardy-Weinberg平衡状态。3个SNP位点的多态信息含量(PIC)为0.25~0.50,表现为中度多态。连锁不平衡分析显示,g.43796424T>A与g.43796425G>T之间存在强连锁不平衡。关联分析显示,g.43796318T>C位点TT和CC基因型个体的初生窝重和初生均重均显著(P<0.05)高于TC基因型;g.43796424T>A位点TA基因型个体的产活仔猪数、初生窝重和断奶仔猪数均显著(P<0.05)高于TT和AA基因型;g.43796425G>T位点GT基因型个体的产活仔猪数、初生窝重和断奶仔猪数均显著(P<0.05)高于GG和TT基因型。双倍型关联分析显示,双倍型H2H4(CCTAGT)个体的产活仔猪数、初生窝重、断奶仔猪数和断奶窝重显著(P<0.05)高于H1H2(TCTAGT)个体和H2H2(CCAATT)个体;双倍型H2H2(CCAATT)个体的初生均重显著(P<0.05)高于除H4H4(CCTTGG)个体外的其他个体,且其断奶均重显著(P<0.05)高于其他双倍型个体。CRISP 3基因第4内含子上的3个突变位点与柯乐猪的6个繁殖性状均存在显著关联,可作为柯乐猪繁殖性状选择的候选分子标记。

To analyze the impact of single nucleotide polymorphism(SNP)loci in the Cysteine Rich Secretory Protein 3(CRISP3)gene on reproductive traits of Kele pigs,Sanger sequencing was used to detect SNP mutations in the CRISP 3 gene of 250 healthy and prolific Kele sows.SPSS 22.0 software was utilized to analyze the association between SNP loci and six reproductive traits in Kele pigs,including total number of piglets born,primary litter weight,average birth weight,weaning litter weight,number of weaned piglets,and average weaning weight.The result showed that in the CRISP 3 gene of Kele pigs,three SNP mutations were identified in the fourth intron(g.43796318T>C,g.43796424T>A,and g.43796425G>T),each having three genotypes.The dominant genotypes for g.43796318T>C and g.43796424T>A were TT,with the dominant alleles being T,while the dominant genotype for g.43796425G>T was GG,with the dominant allele being G.Theχ^(2) test revealed that the genotype distribution of g.43796318T>C was in Hardy-Weinberg equilibrium(P>0.05),whereas the genotype distributions of g.43796424T>A and g.43796425G>T significantly(P<0.01)deviated from Hardy-Weinberg equilibrium.All three SNP loci exhibited moderate polymorphism with polymorphism information content(PIC)ranging from 0.25 to 0.50.Linkage disequilibrium analysis showed strong linkage disequilibrium between g.43796424T>A and g.43796425G>T.The association analysis demonstrated that the TT and CC genotypes of g.43796318T>C were significantly(P<0.05)higher in primary litter weight and average birth weight than those of the TC genotype.The TA genotype of g.43796424T>A had significantly(P<0.05)higher number of piglets born alive,primary litter weight,and number of weaned piglets compared to the TT and AA genotypes.The GT genotype of g.43796425G>T showed significantly(P<0.05)higher number of piglets born alive,primary litter weight,and number of weaned piglets than those of the GG and TT genotypes.In the diplotype analysis,individuals with the H2H4(CCTAGT)diplotype had significantly(P<0.05)higher number of piglets born alive,primary litter weight,number of weaned piglets,and weaning litter weight compared to individuals with the H1H2(TCTAGT)diplotype and H2H2(CCAATT)diplotype.The H2H2(CCAATT)individuals had significantly(P<0.05)higher average birth weight than individuals of other diplotypes except for H4H4(CCTTGG),and its average weaning weight was significantly(P<0.05)higher than that of other diplotypes.The three mutation sites in intron 4 of CRISP 3 gene were significantly associated with 6 reproductive traits of Kole pigs,which could be used as candidate molecular markers for selection of reproductive traits in Kole pigs.