用RAPD技术探讨5种鲷科鱼类的亲缘关系

用RAPD技术对鲷科鱼类的黑鲷、真鲷、二长棘鲷、平鲷和黄鳍鲷进行亲缘关系的研究。在事先优化的反应条件下，在使用的60个随机引物中，有29个引物扩增出清晰稳定的片段，共计200条，大小在200～2500 bp之间。5种鲷均有其特异性扩增片段，可作为种类鉴别的依据。根据MEGA2.1软件的UPGMA和NJ程序构建的分子系统树显示：同属鲷属的黄鳍鲷和黑 鲷的亲缘关系最近，其次是二长棘鲷和真鲷，平鲷与二长棘鲷和真鲷的亲缘关系较近，与黄鳍鲷和黑鲷较远,黑鲷和二长棘鲷的亲缘关系最远。两种聚类的结果相一致。研究结果与借助形态学和生化特征进行的传统系统分析具有一致性。在40个个体之间遗传距离矩阵中，最大值达到0.8916。多数的遗传距离指数在0.50～0.85之间。通过分析，认为RAPD技术对分析属级间的亲缘关系具有一定的适用性。

Study on genetic relationships of Sparidae by RAPD

Random amplified polymorphic DNA(RAPD) technique was applied to study genetic relationships of Sparidae, including Sparus macrocephalus, Parargyrops edita, Pagrosomus major, Rhabdosargus sarba and Sparus latus. Under predetermined optimal reaction conditions,amplifications with 29 random primers selected from 60 primers gave 200 reproducible and stable bands ranging from 200 to 2500 bp. Each species had its own unique bands used for species identification. The molecular phylogenetic trees constructed by UPGMA and NJ methods of MEGA2.1 indicated S. macrocephalus and S. latus that belonged to Sparus were the most related, while S. macrocephalus and P. edita Tanaka were the least; R. sarba was more related with P. major and P. edita than S. macrocephalus and S. latus. Both results were accordant. And they agreed with classical taxonomy based on morphological and biochemical characters. In the matrix of genetic distance resulted from the 40 individuals, the maximal value was 0.8916, and most of them were between 0.50-0.85. The results showed RAPD could be efficient for exploring genetic relationships to some extent.