快速生长转基因黄河鲤品系选育

By more than 10 years′unremitting works from bench to field, we have cultivated 14 pedigrees of the "all-fish"-gh-transgenic Yellow River carp (Cyprinus carpio L.), which exhibit favorable traits, such as fast growth and high efficiency of food conversion. However, the Yellow River carp, as the starting material, was a native population of tetraploid, the phenotype of the sequentially transgenic pedigrees' offspring was not yet uniform. In this project, the offspring of these transgenic pedigrees were employed as pool for selection. By combining with group selection and pedigree breeding methods and using molecular biology and cell biology techniques，we pursue to screen out of fast-growing transgenic strains with body-shape meet with consuming demands and of the partner strains of corresponding wild-type, and establish a breeding system for the transgenic Yellow River carp cultivation. Based on analysis of population genetic structure, we will eventually reveal the molecular biological characteristics of the transgenic Yellow River carp strains and the partner strain of corresponding wild-type, establish molecular identification of transgenic Yellow River carp stains of high farming quality, and finally generate aquaculture species with stable production performance and homogeneous phenotypic characteristics.

经过10多年研究，我们培育了转"全鱼"生长激素基因黄河鲤14个家系，具有生长速度快、饵料转化效率高等优良生产性状。但由于起始材料黄河鲤是野生型的天然四倍体，这些转基因家系子代表现型尚不一致。本研究要以此为材料，整合亲本选育和家系选育方法，运用分子及细胞生物学技术，筛选快速生长、体型符合市场需求的转基因黄河鲤品系及其野生型配套系，建立其优良品系的繁育体系；基于群体遗传结构分析，揭示转基因黄河鲤品系及其配套系的分子生物学特征，建立转基因黄河鲤优良品系的分子标记系统，选育生产性能稳定、表型性状均一的优良养殖品种。

按照本项目研究计划，我们首先通过基因组walking、荧光定量PCR和FISH技术，发现基因鲤鱼基因组外源的GH基因以3个不完整串联重复的形式插入到转基因鱼一条染色体的末端区域，该区域与已知基因没有同源性，整合位点旁侧序列富含AT。随后，本研究针对生长性状发生显著分离的家系，运用极端分离群体测序，筛选出生长性状分离相关候选基因23个，包含多态性SNP标记48个。进而通过基因型/表型关联分析方法和全同胞群体验证，鉴定出生长相关基因2个（17号基因和14号基因）。2个基因的3种基因型（17GG、17GG+14CC和17GG+14TT）亚群体的平均体重与对照群体相比分别增加了27.96%、38.28%和33.72%（P值均<0.05），体重>500g的个体所占比例与对照群体相比分别提高了19.22%、26.82%和30.92%。藉此，我们在该子代群体中选育到了具备优势生长性状的基因型携带者，并获得目标基因型育种群体5000尾以上。