利用RAPD标记研究几种淡水腹足类的亲缘关系

以软体动物腹足纲、中腹足目的光滑狭口螺、长角涵螺、纹沼螺、赤豆螺、大沼螺几个形态分类的近缘种及梨形环棱螺(对照)作为研究对象,用随机扩增多态DNA技术对上述动物进行了20个引物的扩增,共获得117条扩增谱带,单个引物扩增的RAPD标记在3-12个之间,片段长度在30—3000bp之间。试验结果显示：淡水螺类的RAPD标记具有明显的多态性,而且种间的扩增标记及差异程度可以反映出物种间系统演化过程的亲缘关系。通过数值聚类制图后得到：长角涵螺、纹沼螺、大沼螺、赤豆螺之间的亲缘关系较近,而光滑狭口螺、梨形环棱螺与上述4个种的亲缘关系较远,其结果与新修订的淡水中腹足目科级分类方案相当吻合。

Phylogenetic Relationships Among Some Freshwater Gastropoda as Revealed by RAPD Marks

Phylogenetic relationships between 6 freshwater snails, Stenothyra glabra,Alocinma longicornis,Parafossarulus striatulus,Bithynia fuchsiana,Parafossarulus eximius and Bellamya purificata (Gastropoda, Mesogastropoda) were studied in detail using random amplified polymorphism DNA (RAPD). Using twenty 10?bp random primers a total of 117 marks, ranging from 340 to 3 000 bp, were produced from these 6 species of snails. The variation of RAPD marks in the different species was high. The differentiation of RAPD marks in these different species of snails demonstrates the correlationships in freshwater Gastropod phylogeny. Cluster analysis indicates that Alocinma longicornis,Parafossarulus striatulus,Parafossarulus eximius and Bithynia fuchsiana are much more closer compared to Stenothyra glabra and Bellamya purificata, the latter belonging to a different family. The results coincide with the recent modified taxonomical system for the freshwater Mesogastropoda.