猪背膘厚主效基因捕获及变异序列构建

项目名称： 猪背膘厚主效基因捕获及变异序列构建

项目编号： No.31201781

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 畜牧学与草地科学、兽医学、水产学

项目作者： 张龙超

作者单位： 中国农业科学院北京畜牧兽医研究所

项目金额： 24万元

中文摘要： 中外猪种背膘厚的巨大差异有着极其复杂的分子遗传机制。申请人前期在构建的大白猪×F2设计资源群体中，运用全基因组关联研究（GWAS）方法，检测发现7号染色体上存在8个与背膘厚性状显著关联的SNP位点，区间跨度1.8Mb，包含了24个已知基因。本项目旨在及时利用前期研究的成果，通过DNA水平、RNA表达水平开展背膘厚性状主效基因捕获。拟利用单倍型分析、选择性清除分析获得最小显著区间，通过民猪、大白猪GWAS区间内所有基因表达规律及表达差异研究缩减候选基因数量，结合生物信息学综合分析捕获主效基因。以主效基因所在单倍型开展关联分析，以H+民猪、H-大白猪分别作为QQ、qq型个体，开展主效基因全基因序列片段靶向捕获及重测序，获得两猪种间变异位点，构建出猪种间变异位点序列。本项目的实施不但为动物复杂性状GWAS后捕获主效基因方法研究方面有重要理论意义，且为以降低背膘厚为目的的分子选育提供理论基础。

中文关键词： 背膘厚；全基因组关联研究；HMGA1；主效基因；猪

英文摘要： As we all know, most Chinese indigenous pig breeds (fat type) own more thicker backfat (>4 cm) than Western commercial pig breeds (meat type) (<2 cm). The mechanism of inheritance for backfat thickness is very complex. A genome-wide association study (GWAS) has been applied to detect the SNPs associated with backfat thickness in a Large White ×inzhu F2 design population. Our previous results indicated that eight SNPs in a 1.8 Mb region on SSC7 showed genome-wide significant association with backfat thickness. Twenty-four annotated genes were contained in this region. According to the pre-existing results, the aim of present project is to capture the major gene for backfat thickness throughout the study in DNA and RNA level. For DNA level, haplotype sharing analysis and selective sweep analysis will be applied together to refine the region from previous GWAS result. For RNA level, Those genes that are not expressed or with low level in backfat tissues in both Minzhu and Large White will be eliminated. Significantly tests will be done for all retained genes express level at 60, 120, 150, 180 and 200 d between Minzhu and Large White. Synthesizing the obove information, the major gene of backfat thickness will be captured in the significant region from GWAS. Several individuals of Minzhu with H+ and Large White wi

英文关键词： backfat thickness；GWAS；HMGA1；major gene；pig