39例足癣复发后病原菌核糖体基因序列变化

The changes of DNA sequence of pathogen after relapse in athlete's foot

目的:检测红色毛癣菌足癣复发后致病菌株基因型的变化。方法:对39例红色毛癣菌足癣复发后进行红色毛癣菌核糖体保守区(部分5.8s和ITS-2)和非转录间隔区(NTS)内的两个重复亚单位(TRS-1,TRS-2)进行PCR扩增,基因序列测定。结果:39株红色毛癣菌复发前后和标准株保守区基因序列测定比较,同源性均达99%,均为红色毛癣菌;(NTS)内的两个重复亚单位(TRS-1,TRS-2)基因序列测定比较,其中3株菌TRS-1区存在个别碱基突变,3株TRS-1区存在重复序列拷贝数变异,1株菌TRS-2区存在个别碱基突变。结论:复发后的红色毛癣菌基因型基本稳定,说明足癣复发大部分与原浅表真菌复燃有关。

Objective：To determine the changes of DNA sequence of Trichophytin rubrum after relapse in athlete＇s foot. Methods：Two epetition subunits（ TRS-1,TRS-2） of Trichophyton rubrum ribosomal non-conservertive region NTS were amplified by PCR and followed by gene sequencing in 39 patients with relapsed athlete＇s foot. Results：The Trichophyton rubrum ribosomal non-conservative region NTS in the first and the second isolates of tinea pedis was very close （ the isogeny was 99%） . Individual base mutation happened in TRS-1 region of 3 cases or TRS-2 region of 1 case. Copy number of gene duplication sequence in TRS-1 region of ribosomal non-conservative region was seen in 3 cases. Conclusion： The genotype of Trichophyton rubrum is stable in the isolates of the patients with relapsed tinea pedis. Recurrence of tinea pedis was most likely caused by the existing fungi rather than new infections with other stains of fungi.