绵羊HLF基因多态性及其与肌肉脂肪酸、氨基酸含量的关联分析

Analysis of sheep HLF gene polymorphism and its correlation with muscle fatty acid and amino acid content

为了研究人乳铁蛋白(human lactoferrin,HLF)基因多态性对绵羊肉质性状的影响,试验以双乾肉羊为研究对象,采用Sanger测序方法寻找HLF基因第2外显子序列的SNP位点,检测HLF基因多态性,分析不同基因型与脂肪酸和氨基酸含量的关联性。结果表明:在绵羊HLF基因第2外显子序列179 bp处存在A>C突变,且为同义突变,存在AA、AC和CC 3种基因型,相应频率分别为30.6%、57.1%和12.2%,其中AC为优势等位基因型;有A和C 2个等位基因,相应频率分别为40.8%和59.2%,其中C为优势等位基因。A>C SNP位点均处Hardy-Weinberg平衡(P>0.05);杂合度(He)为0.4831,有效等位基因数(Ne)为1.9345,纯合度(Ho)为0.5169,该位点属于中度多态(0.250.05)。说明HLF基因多态性对脂肪酸及氨基酸含量有一定影响。

To investigate the effects of human lactoferrin(HLF)gene polymorphism on meat quality traits of sheep,in this study,Sanger sequencing method was used to find the mutation site of HLF gene exon 2 sequence and analyzed its association with meat quality traits and fatty acid content indexes.The results show that:A/C mutation was found in 179 bp of exon 2 of sheep HLF gene,and the mutation was synonymous.There were three genotypes AA,AC and CC with genotype frequencies of 30.6%,57.1%and 12.2%,respectively.The gene frequencies of two alleles A and C were 40.8%and 59.2%,respectively,so AC was the dominant allele,and C was the dominant allele.Hardy-weinberg equilibrium was found in all A/CSNP loci(P>0.05).The heterozygosity(He)was 0.4831,the effective number of alleles(Ne)was 1.9345,and the homozygosity(Ho)was 0.5169,indicating that the locus was moderately polymorphic(0.25<PIC<0.5).The contents of palmitic acid,heptadecanoic acid and oleic acid in AA type were significantly higher than those in AC type(P<0.05),and tyrosine in CC type was significantly higher than that in AC type(P<0.05).There were no significant differences in other traits among different genotypes(P>0.05).In conclusion,HLF gene polymorphism had a certain influence on fatty acid and amino acid content.