贵州白山羊DQB1基因外显子3的多态性及生物信息学分析

Polymorphism and Bioinformatics Analysis of DQB1 Gene' Exon 3 in Guizhou White Goat

为筛选贵州白山羊DQB1基因外显子3序列的SNPs位点,并进一步研究MHC基因多态性与山羊免疫性状的相关性奠定基础,以贵州白山羊为研究对象,采用混合DNA池与直接测序相结合对DQB1基因外显子3多态性及生物信息学进行分析。结果表明:贵州白山羊DQB1基因外显子3中有17个SNPs位点,其中,G+115A(Arg→Gln)、C+156T(Leu→Phe)、G+206A(Met→Ile)、G+238A(Arg→His)和T+270A(Ser→Thr)位点为错义突变;C+20T位点具有最小的自由能,其RNA二级结构最为稳定;各基因型蛋白质二级结构均由β折叠和无规则卷曲构成且比例相近,易于抗原决定簇的形成;参考序列与错义突变5种基因型均存在5段抗原决定簇,且均具有较高的平均抗原倾向性。

The polymorphism and bioinformatics of DQB1 gene＇exon 3 were analyzed by the combination method of mixed DNA pool and direct sequencing to screen SNPs loci of DQB1 gene＇exon 3in Guizhou White Goat and lay a foundation for further studying the correlation between polymorphism of MHC gene and immune character in Guizhou White Goat.Results：There are 17 SNPs loci in DQB1gene＇exon 3of Guizhou White Goat.G＋115A（Arg→Gln）,C＋156T（Leu→Phe）,G＋206A（Met→Ile）,G＋238A（Arg→His）and T＋270A（Ser→Thr）belong to missense mutation.C＋20Tlocus is of the minimum free energy and its RNA secondary structure is most stable.The protein secondary structure of different genotypes is structured byβ-strands and random coil with the similar proportion,which is liable to formation of antigenic determinant.There are 5antigenic determinants with higher average antigenic tendentiousness in reference sequence and 5missense mutation genotypes