MGE-PCR分析不同临床表现的阴道毛滴虫分离株

MGE-PCR in Analyzing the Genetic Characteristics and the Clinical Manifestation of Trichomonas vaginalis Isolates

目的分析引起不同临床表现的阴道毛滴虫分离株的遗传特性。方法用移动遗传因子(mobile geneticelements,MGEs)-PCR技术对30个不同临床表现的阴道毛滴虫分离株(轻度3株、中度22株、重度5株)基因组进行扩增,用邻位相连法(neighbor joining,NJ)对扩增产物进行聚类分析。结果阴道毛滴虫分离株间的遗传差异明显,遗传距离在0～1间均有分布,平均遗传距离为0.69,根据遗传距离构建的树状聚类图有3大聚类,临床表现轻度组(Tv4、Tv14和Tv26)分布于聚类2;重度组(Tv10、Tv15、Tv13、Tv21和Tv25)分布于聚类1;除了Tv2、Tv5、Tv17和Tv28外,其余18株均属于进化树顶部的大分支(聚类3)。。其中Tv12和Tv29、Tv18和Tv20、Tv14和Tv26、Tv10和Tv25、Tv15和Tv21的遗传关系最为密切,遗传距离为0。结论 30个阴道毛滴虫分离株基本上是按照引起临床表现轻重差异而聚类的,提示阴道毛滴虫引起的临床表现与其基因差异性有关。

Objective To analyze the genetic characteristics of Trichomonas vaginalis isolates causing different clinical manifestation.Method Mobile genetic factor （MGE）-PCR technique was used for genome amplification in 30 isolates of Trichomonas vaginalis with different clinical manifestation （mild 3,moderate 22,severe 5）,and neighbor joining method （NJ）was applied for cluster analysis of the amplified products.Results Significant genetic differences were revealed among the isolates,with a distance ranging from 0 to 1 and an average genetic distance of 0.69.A dendrogram based on the genetic difference among the isolates formed 3 clusters.Those with severe or mild clinical manifestation located in cluster 1 （Tv10,Tv15,Tv13,Tv21,and Tv25）or cluster 2 （Tv4,Tvl4,and Tv26）,respectively. The other 18 isolates,except Tv2,Tv5,Tvl7,and Tv28,all distributed in the cluster 3 at the top of the large branches of the tree.Close genetic relationship was found in 5 groups with a genetic distance of 0：Tvl2 and Tv29, Tvl8 and Tv20,Tvl4 and Tv26,Tv10 and Tv25,Tv15 and Tv21.Conclusion The clustering of the 30 T.vaginalis isolates is related to the degree of clinical manifestation that they caused,indicating a possible relationship between morbidity and the gene difference of the parasite.