中国大陆日本血吸虫随机扩增多态DNA(RAPD)的初步研究

RAPD FINGERPRINTINGS FOR PHYLOGENETIC RELATIONSHIP AND ISOLATES IDENTIFICATION OF SCHISTOSOMA JAPONICUM IN China's Mainland

目的对中国大陆浙江、安徽、江西、湖北、湖南、四川、云南7省日本血吸虫种群进行遗传变异研究。方法应用随机扩增多态DNA（RAPD）技术，对5条寡核苷酸随机引物扩增。结果获得32条DNA片断，17个基因位点，长度在100bp～2600bp之间。各种群多态百分率（P）为52．9～70．6，平均杂合性（H）为0．269～0．363。中国大陆湖区日本血吸虫各种群间遗传距离（D）为0．000～0．023．山区种群间为0．155，湖区种群与山区种群间遗传距离为0．036～0．139。同时，P235-930bp，P293－910bP分别为四川种群和云南种群特异性DNA片断，P256－720bp为日本血吸虫雌虫特异性DNA片断。对中国大陆日本血吸虫虫株复合性和系统发生作简要讨论。

Objectives To detect genetic variation of seven isolates of Schistosoma japonicum from Zhejing, Anhui, Jiangxi, Hunan, Hubei, Sichuan. Yunnan provlnces in China's Mainland. Methods A random amplified polymorphic DNA (RAPD) technique was performed in the study by using 5 random oligonucleatide primers and data analysis were performed by Nei's genetic distance (D). Re sults 17 loci including 32 reproducible DNA fragments were detected. The percentages of loci polymorphic (P) were 52. 9~70. 6 and mean heterozygosity per locus (H) were 0. 269~0. 363 in seven isolates of S. japonicum. Nei's genetic distance (D ) between 5 isolates from marshland-lake regions ranged from 0.000~0.023, between two isolates from mountainous-hilly regions was 0.155. between the isolates of marshland-lake regions and mountalnous-hilly regions ranged from 0.036~0.139. Meanwhile. specific DNA fragments, P235-930bp. P239-910 bp, P256-720 bp, were reported as isolate markers and sex marker respectively. The results of this research leads to discus sion on strain complex and phylogeny of S. japonicum in China's Mainland.