阿坝藏猪蒲江种群SLA-DRB基因片段SNP检测及其与生长发育性状关联分析

Single Nucleotide Polymorphisms of the Partial Sequence of SLA-DRB Gene in Pujiang Population of Tibetan Pigs and Correlation with Growth Traits

猪Sus scrofa domesticus的白细胞抗原复合体(SLA)基因的单核苷酸多态性(SNP)与猪生长发育等性状有关。为了开发藏猪品系选育的遗传标记,本文测定了阿坝藏猪蒲江种群89头个体的SLA-DRB基因部分序列,共鉴定出14个SNP位点。根据位点间的连锁强度分为3个组合(组合1:g. 11470、g. 11945、g. 11997、g. 11387、g. 11369与g. 11829;组合2:g. 11532与g. 11838;组合3:g. 11911与g. 11708)和4个独立多态位点(g. 11468、g. 11440、g. 11478和g. 11944)。将基因型与体质量、体长等14项生长发育性状进行关联性分析,结果表明,组合3的基因型与体高、体长、胸围等11项体尺指标间的相关性均显著(FDR <0. 05),基因型为TT/CG的个体较小,表明SLA-DRB基因可用于藏猪小型化选育的遗传标记。管围和12项管围率(除体质量以外)与SLA-DRB基因多态性的相关性最高,受组合1、组合2和位点g. 11468、g. 11478基因型的极显著影响(FDR <0. 001),其中,基因型为组合1=GGGAAC/GGGAAC、组合2=GT/GT、位点g. 11468=C/C和g. 11478=C/C的个体拥有更大的管围和管围率。管骨骨髓是SLA基因发挥免疫功能的主要场所之一。本研究为基于管围的猪种筛选提供了理论依据和可用的SNP位点,也为藏猪抗病遗传筛选提供了基础数据和参考资料。

The single nucleotide polymorphism(SNP)of swine leukocyte antigen(SLA)gene is associated with the growth and development traits of swine.In this study,the partial sequence of SLA-DRB gene of 89 Aba Tibetan pigs(Pujiang county,Sichuan province)was sequenced to screen the stable markers for genetic breeding,and 14 loci of SNPs were identified.Based on the linkage relationships,these 14 loci of SNPs were allocated into 3 groups(loci group 1:g.11470,g.11945,g.11997,g.11387,g.11369 and g.11829;loci group 2:g.11532 and g.11838;loci group 3:g.11911 and g.11708)and 4 single polymorphic loci(g.11468,g.11440,g.11478 and g.11944).Correlation analyses were conducted between the genotypes of these loci or loci groups and 14 growth traits(i.e.body mass and body length).The polymorphism of loci group 3 was significantly associated with 11 growth traits(FDR<0.05),including withers height,body length and chest circumference,and the individuals with genotype TT/CG had smaller somatotype than that of others.This suggested that SLA-DRB gene might be a stable genetic marker for the miniaturization selection of Tibetan pigs.The cannon bone circumference(CBC)and ratios of CBC to other growth traits(except body mass),were tightly associated with the polymorphism of loci group 1,loci group 2,g.11468 and g.11478(FDR<0.001).The individuals with genotypes GGGAAC/GGGAAC at loci group 1,GT/GT at loci group 2,C/C at g.11468 and C/C at g.11478 tend to have large CBC and CBC ratios.Given that the cannon bone marrow is a major site for the immune function of SLA genes,our results here provide theoretical basis and stable SNP loci for CBC based swine selective breeding and disease resistance oriented genetic breeding.