猪生长和胴体性状是最重要的经济性状之一。然而生长和胴体性状均为复杂性状，国际上第一个报道的家猪4号染色体上影响生长及脂肪沉积的QTL至今已23年，其因果基因至今仍未被解析。申请人所在实验室黄路生院士自2006年起，设计并构建了国际上唯一的中外极端差异表型的八个品种家猪嵌合家系，为解析复杂性状提供了独特的遗传资源，申请人是该嵌合群体的主要执行人之一，并于近期对该群体近1000头F6代个体进行了230个表型性状的精准测定，初步分析在4号染色体上发现了显著影响生长及胴体性状的QTL区域，本项目将通过基因组全序列，肌肉及肝脏的转录组和血液代谢组等组学分析，结合本实验室前期构建的F2资源家系群体和杜长大商业群体数据，解析猪4号染色体影响生长和胴体性状的因果基因。

Growth and carcass characteristics are among the most important traits in pigs. However, both growth and carcass traits are complex, it has been 23 years since the first quantitative trait loci (QTL) for growth and fatness traits were reported in 1994, the causative gene of this loci remains unclear. The director of the lab where the applicant work, Professor Lusheng Huang, have designed and organized to build up an unique pig heterogeneous stock population with 8 founder breeds encompassing both Chinese indigenous pig breeds and Western commercial breeds that displayed marked phenotypic diversity since 2006. This population provide an important and unique resources to investigate genetic basis of complex traits in pigs. The applicant is one of main investigator of the pig heterogeneous population. Recently, the applicant have organized to measure 230 phenotypes on about 1000 F6 individuals from the heterogeneous stock population. Initial genome wide association analyses allowed us identified a significant QTL for growth and carcass traits on chromosome 4. In this study, we aimed to identify the causative gene underlying the QTL on chromosome 4 through integrative analysis of whole genome sequence data, transcriptome of liver and muscle tissues, metabolome of blood and data from F2 resource population and Duroc-Landrace-Yorkshire hybrid population that were constructed previously.