贵州白山羊GOLA-DQA1基因多态性及生物信息学分析

Polymorphism and Bio-information of GOLA-DQA1 Gene in Guizhou White Goat

目的:通过筛选贵州白山羊GOLA-DQA1基因SNPs位点,为进一步研究MHC基因多态性与山羊免疫性状的相关性提供依据。方法:选取同一生长环境中的贵州白山羊母羊157只构建品种DNA池并进行测序,结合SNPs位点测序峰高比值估算等位基因频率,利用软件对不同基因型的RNA和蛋白质二级结构进行预测。结果:在贵州白山羊DQA1基因发现6个SNPs位点G+2930A(同义突变)、T+2959C(Asn→Ser)、G+3061A(Pro→Leu)、A+3082G(Me→Thr)、C+3463A(Trp→Cys)、C+3525T(Arg→His)。生物信息学分析发现,C+3463A变异位点使RNA二级结构更加稳定;A+3082G变异导致自由能增加,稳定性降低。蛋白质结构预测发现除A+3082G基因型与原序列具有相同的二级结构外,其他基因型均引起蛋白质二级结构的改变。结论:贵州白山羊GOLA-DQA1基因具有丰富的多态性,但SNPs位点等位基因频率差异较大。

Objective：SNPs of GOLA - DQA1 gene in Guizhou White Goat were detected in order to provide a theoretical foundation further studying on genetic polymorphisms of relations between MHC gene and immune character in goats. Method：157 goats grow in the same condition were used to construct DNA pooling. The allele frequencies of SNP in each breed were estimated by DNA sequencing and calculating the ratio of allele peak heights. The RNA secondary structure and protein secondary structure of different genotypes were predicted by the online software. Result：Four SNPs were identified in the exon3, they are G ＋ 2930A （same sense mutation） , T ＋ 2959C （Asn→Ser） , G ＋ 3061A（ Pro→Leu）, A ＋ 3082G（ Met→Thr）, two SNPs were identified in the GOLA -DQAI gene exon4, they are C ＋ 3463A （Trp→ Cys）, C ＋ 3525T （Arg-→His）. By bio -information, we found C ＋ 3463A locus mutation makes structure more stable, free energy in A ＋ 3082G site is increased, but the stability is lower. By protein structure prediction, A ＋ 3082G genotype and the no mutation genotype have the same secondary structure, but other genotypes have different protein secondary structures. Conclusion： Guizhou white goat GOLA - DQA1 gene has rich polymorphism, but there was great difference among SNPs locus allele frequency.