中文摘要：

本研究旨在利用全基因组关联分析方法（genome—wideassociationstudies，GWAS）挖掘影响绵羊体重性状的遗传标记和功能基因。采用IlluminaOvineSNP50BeadChip中密度商业化羊芯片，对3个品种（苏尼特羊、德国肉用美利奴羊和杜泊羊）共计329只绵羊的体重性状（初生重、断奶重、6月龄重、断奶前日增重、断奶后日增重、日增重）进行GWAS分析。统计分析和基因注释基于TASSEL软件、混合线性模型和2012年10月公布的最新版绵羊基因组Ovis-aries-v3．1序列信息。结果表明，有10个sNPs位点在全基因组显著水平上与断奶后日增重相关，部分位点分布在羊注释基因内（MEF2B、RFxANK等）；除此之外还检测到22个SNPs在染色体显著水平上与其他体重性状存在相关性，获得一批重要的候选基因。这些基因对绵羊体重性状功能基因的挖掘具有重要的理论意义和参考价值。

英文摘要：

Motivated by mining major candidate genes across Ovine genome, the present study is to perform genome-wide association studies（GWAS） to detect genes associated with body weight traits. Using Illumina OvineSNP50 BeadChip, we per- formed a GWA study in 329 purebred sheep phenotyped for 6 body weight traits（birth weight, weaning weight, 6-month weight, pre-weaning gain, post-weaning gain, daily weight gain）. Statistics and data analysis were based on TASSEL pro- gram,mixed linear model and the latest Ovis_aries_v3.1 genome sequence （released October 2012）. The results indicated that 10 SNPs consistently reached genome-wise significant level for post-weaning gain and 22 SNPs reached chromosome-wise signif- icant level for other body weight traits. The SNPs were within （MEF2B,RFXANK,et al） or close to some ovine genes, which were thought to be the most important candidate genes associated with body weight traits. The results will contribute to identi- fy candidate genes for ovine body weight traits, and facilitate the potential utilization of genes involved production traits in sheep in future.