团头鲂红体色突变体的发现及其种质遗传分析

以自然环境下发现的5尾红色鳊鱼(雌鱼3尾,雄鱼2尾)为材料,进行种质遗传鉴别。形态可数性状测定显示,红色鳊鱼胸鳍条数为14,背鳍和臀鳍棘数均为2,而其他6群体鳊鲂鱼类(东江三角鲂、钱塘江三角鲂、广东鲂、团头鲂、厚颌鲂和长春鳊)的胸鳍条数为16-19,背鳍和臀鳍棘数均为3。对9项形态学可量比例参数和20项框架参数进行主成分分析,显示红色鳊鱼突变体在这些形态上与团头鲂较近。微卫星聚类分析发现,红色鳊鱼突变体首先与团头鲂聚类,遗传距离最近,为0.309 4,与长春鳊的遗传距离最远,为3.743 9。最后,通过线粒体COX1和COX2基因序列分析,发现这5尾突变体与团头鲂的遗传相似度高达99%,与三角鲂、长春鳊、大眼华鳊、翘嘴鲌、蒙古鲌、鲫、鲤和斑马鱼的遗传相似度分别为95%、95%、94%、94%、93%、86%、86%和82%,聚类分析结果也显示红色鳊鱼突变体首先与团头鲂聚类,表明红色鳊鱼突变体与团头鲂间存在极近的亲缘关系,应属于团头鲂的体色突变类型。团头鲂红色突变体可为团头鲂的遗传育种研究提供宝贵的研究材料。

Discovery of red body color mutants in Megalobrama amblycephala and their genetic analysis

In this study, genetic analysis was performed for five new red body color bream mutants (two males and three females) from the natural environment. By measure countable morphological traits, the soft ray number of dorsal fin, the spine number of dorsal fin and anal fin in red color bream mutants are 14, 2 and 2 respectively, whereas those in other 6 Megalobrama and Parabramis species (M. terminalis from Dong river, M. terminalis from Qiantang river, M. hoffmanni, M. amblycephala, M. pellegrini and P. pekinensis) are 16-19, 3 and 3, respectively. Principal component analysis show the red color bream mutants have a close relationship with M. amblycephala based on 9 measurable proportion parameters and 20 frame parameters. Microsatellites analysis demonstrated that the red color bream mutants and M. amblycephala firstly grouped together, and their genetic distance was 0.3094. The genetic distance between the red color bream mutants and P. pekinensis was 3.7439, which was the farthest. Finally, the genetic similarity between the red bream mutants and M. amblycephala, M. terminalis, P. pekinensis, Sinibrama macrops, Culter alburnus, Chanodichthys mongolicus, Carassius auratus, Cyprinus carpio and Danio rerio are 99%,95%,95%,94%,94%,93%,86%,86% and 82% respectively, by sequence analysis from mitochondria COX1 and COX2 genes. Cluster analysis results also show the highly close relationship between the red bream mutants and M. amblycephala, indicating the red body mutants may have originated from M. amblycephala. The red M. amblycephala could provide valuable materials for future genetic breeding of M. amblycephala.