低等鲤科鱼类RAPD分析及系统发育研究

THE RAPD ANALYSIS AND THE PHYLOGENETIC CONCERNING FOR PRIMITIVE CYPRINIDAE

通过对鲤科鱼类30个个体所代表的18个种的随机扩增，作者得到了大量有系统发育信息的DNA多态片段。通过Rapdplot程序将DNA的多态片段转换成遗传距离（d=1－S，S＝2NxNy／Nx＋Ny）。该遗传距离的矩阵经PHYLIP软件包中的Neighbor（option=NJ）程序处理后，生成了低等鲤科鱼类代表属种的分支系统图。从该系统图可以看出：RAPD分析方法在鲤科鱼类的系统发育研究中有一定的局限性，它比较适合于亚科内属间系统发育的研究。结果显示亚科并不是一个单元类群，其中的马口鱼类和细鲫类各自形成单元群，但这两个类群间的关系并不直接联系。在分析结果中，分布于东亚的雅罗鱼亚科鱼类比亚科鱼类更原始。

Many informative fragments of the RAPD were obtained from 30 individuals that representing 20 species of the primitive cyprinid fishes by the method of random amplifying with 20 primers. We converted the DNA polymorphic fragment into genetic distance by the program Rapdplot (d=1-S, S=2NxNy/Nx+Ny). The prograxns Neighbor in software package PHYLIP was used to calculated the matrix of genetic distance resulted which in one cladogram of 20 species. It is indicated that the application of the RAPD analysis for Cyprinidae may have some limitations. For the inter-genera analysis in same subfamily, the result is reliable. The result of the RAPD analysis indicates that: the subfamily Danioinae is not a monophyletic group.Among them, the Zacco group and Aphyocypris group form monophyly respectively. And in this subfamily, the two groups do not have a direct relationship.