随机扩增多态性DNA技术对我国大陆光壳钉螺遗传多样性的初步探讨

目的探索随机扩增多态性DNA(RAPD)技术对大陆光亮钉螺遗传多态性研究的可行性,以获得不同地区光壳钉螺基因组DNA水平上的差异信息。方法随机引物对大陆光亮钉螺基因组DNA进行PCR扩增,产物经8％聚丙烯酸胺凝胶电泳、0.6％的硝酸银染色,记录结果并分析。结果 2条引物S15(5’CATGCAGGCG3’)、S18(5’ACAGCCTGCT3’)在螺群间显示出多样性,并且扩增结果稳定可重复。对9个地区钉螺共扩增出82个条带,19.51％的条带为9个地区螺群所共有。S15扩增结果中,云南和四川的螺群在 770bp、390bp处均有特异性条带产生,另外四川在570bp处产生其它螺群均没有的条带。S18的扩增产物中,福建福清的钉螺400bp以下无条带产生。云南和四川的螺群分别在380bp与400bp处产生特异性条带,在750bp处产生共有的特异性条带。而江苏东台和福建福清的钉螺在950bp处产生其他地区的钉螺所没有的特异性条带。这些特异性的条带和特征在同一采集点个体间可以重复。结论RAPD技术可为钉螺的遗传变异分析研究提供分子水平上的信息。我国各地光壳钉螺间存在较大的遗传变异,其变异程度和钉螺采集地的地理分布有一定的关系。

Preliminary study on genetic diversity of smooth-shelled Oncomelania hupensis from mainland of China by random amplified polymorphic DNA technique

Objective Using RAPD technique to study genetic diversity of smooth-shelled Oncomelania hu- pensis in China and to gain more information on genome DNA level. Methods Genomic DNA was amplified by random primer and the products were electrophoresed by 8% polyaerylamide and stained by 0.6% silver nitrogen. Results Two primers showed stable and repeatable characters among different individuals from the same location and genetic diversity among different populations: S15 (5'CATGCAGGCG3'), S18 (5'ACAGCCTGCT3'). The total number of bands amplified by S15 and S18 was 82, and 19.51% of them were shared by all of snail popula- tions. Special bands With 390 bp and 770 bp obtained by primer S15 were found in Yunnan and Sichuan snail populations. A 570 bp-sized band was only obtained in snails from Sichuan. From DNA finger printing amplified by S18, bands of 380 bp and 400 bp were revealed in snails of Yunnan and Sichuan, respectively. A band of about 750 bp was found only in Yunnan and Sichuan snails, and there were no bands less than 400 bp in snails from Fujian. A band with 950 bp was amplified only in snails from Dongtai, Jiangsu and Fuqing, Fujian. These special bands and characteristics could be repeated in different individuals in the same localities. Conclusion RAPDs can be used to provide molecular information for the genetic diversity study of Oncomelania. There is large genetic diversity among smooth-shelled snails in China and the level of diversity has correlation with the geo- graphical distribution of sampling snails areas.