半滑舌鳎是我国鲆鲽鱼类养殖产业的主导品种之一。近年来，各类病害问题日益严重，尤其是由爱德华氏菌、哈维氏菌等病原菌引起的疾病频发，已成为制约半滑舌鳎养殖业可持续发展的瓶颈。抗病力作为鱼类重要的经济性状，其分子机理的解析是抗病育种的重要前提，而抗病功能基因和分子标记的发掘又是进行抗病分子机理解析的重要基础。本项目拟以半滑舌鳎为材料，在已完成的全基因组精细图谱、高密度SNP遗传连锁图谱的基础上，开展抗细菌病相关QTL精细定位，鉴定出抗细菌病相关主效功能基因，采用基因组编辑、表观遗传学等途径阐明抗病基因功能，构建抗病基因调控网络，揭示半滑舌鳎抗病性状的分子机理；进而利用半滑舌鳎抗病和易感家系开展基因组重测序，筛选抗病相关SNP位点，进行全基因组关联分析，建立抗病性状全基因组选择育种的理论基础。本项目成果将为鱼类抗病分子育种奠定理论基础和提供技术支撑，将推动我国鱼类抗病育种学科发展及抗病育种的进程。

Half smooth tongue sole (Cynoglossus semilaevis) is an important species of flatfish. Recent years, the problem of disease occurrence, especially the disease caused by Edward's and vickers bacteria, has become a main limiting factors for sustainable development of half smooth tongue sole aquaculture in China. Disease resistance is an important trait in farmed fishes, and the urgent problems to solve at the moment are to create and breed the fish species with excellent disease resistances. Research on molecular mechanism of disease resistance in fish is an important guarantee of new variety breeding. And the finding of disease resistance-related functional genes and molecular markers is an important foundation of researching on molecular mechanism of disease resistance. In view of above, based on the availability of whole genome fine map and high density SNP genetic linkage map in half smooth tongue sole, the present project focuses on identification the main functional genes resistant to main bacterial pathogens by QTL fine mapping, transcriptome and proteome analysis; exploration of the disease resistant genes function through genome editing, RNA inference and epigenetics; determination disease-resistant gene regulatory networks; and revelation the molecular mechanisms of disease resistance in half smooth tongue sole. And then, we will carry out whole genome re-sequencing for the produced families and population to screen disease resistance-related SNP loci, implement genome wide association study (GWAS) and develop genomic selection (GS) breeding theory for half smooth tongue sole. The project will provide a theoretical basis and a technical support for breeding new stock with enhanced disease resistant in fish.