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目的：通过核型分析探讨中国利什曼原虫分离株遗传变异情况。方法：应用脉冲电泳技术对１６株中国利什曼原虫分离株基因组核型进行分析。结果：被测分离株分有１４条－２６条染色体（低于２２００ｋｂ）被区分，核型差异大多集中于２２５ｋｂ－８５０ｋｂ染色体区域，较大染色体相对保守。其中１４株属于杜氏利什曼原虫复合体的分离株存在明显的种内核型差异，但来自同一流行区的分离株核型显示差异较小。所有杜氏利什曼原虫复合体的分离株均含有１１条相似染色体带：３２０ｋｂ，３５０ｋｂ，３８０ｋｂ，８７０ｋｂ，９１０ｋｂ，１０７０ｋｂ，１２００ｋｂ，１２５０ｋｂ，１３５０ｋｂ，１６００ｋｂ和１９００ｋｂ。其中，从白蛉体内分离出的７７１分离株核型显示较为独特，共分离出２６条染色体带。另两株从大沙鼠体内分离的、先前已分被命名为沙鼠利什曼原虫和都兰利什曼原虫的Ｒ１２和Ｒ２０分离株显示相近核型。结论：中国杜氏利什曼原虫复合体内存在明显种内遗传变异，但亲缘关系越近的分离株核型也越相近。地理环境与媒介白蛉均对杜氏利什曼原虫复合体内遗传变异起一定作用。Ｒ１２和Ｒ２０分离株倾向于属于同一个种或两个亲缘关系极近的种。同时，可见寄生的哺乳动物宿主不同可能与利什曼?
Objective: To explore the genetic variation of Leishmania china isolates by karyotype analysis. Methods: The genomic karyotypes of 16 Chinese Leishmania isolates were analyzed by pulse electrophoresis. Results: There were 14 - 26 chromosomes (less than 2200kb) in the tested isolates. The majority of karyotypes were located in the 225kb-850kb chromosomal region, while the larger chromosomes were relatively conserved. Among 14 isolates belonging to Leishmania donovani, there were obvious intraspecific karyotype differences, but isolates from the same epidemic area showed little difference in karyotype. All isolates of Leishmania donovani isolate contained 11 similar chromosomal bands: 320kb, 350kb, 380kb, 870kb, 910kb, 1070kb, 1200kb, 1250kb, 1350kb, 1600kb and 1900kb. Among them, the karyotype of the 771 isolate isolated from the body of white catfish showed a rather unique pattern, with a total of 26 chromosome bands isolated. The other two R12 and R20 isolates, isolated from the large gerbil, previously divided into Leishmania rhamnosus and Leuconostoma leishmanii, showed similar karyotypes. Conclusion: There are obvious intraspecific genetic variations in the Leishmania donovani complex, but the closer the kinship, the closer the karyotypes are. Geographical environment and white catfish all play a role in the genetic variation of Leishmania donovani complex. R12 and R20 isolates tended to belong to the same species or two closely related species. At the same time, it can be seen that different parasitized mammalian hosts may be associated with Leishman?