我国内脏利什曼病山丘疫区与平原疫区利什曼原虫SSUrDNA多变区序列分析

目的 ]分析我国内脏利什曼病 (VL)山丘疫区与平原疫区利什曼原虫 (L .d )分离株小亚基核糖体DNA (SSUrDNA)多变区的序列差异。 方法 ]nDNA进行PCR扩增 ,将扩增出的SSUrDNA基因的特异片段克隆于 pGEMR TEasyVector上 ,采用通用引物M 13进行PCR扩增 ,全自动测序仪测序。 结果 ]序列分析显示 ,扩增的 5株利什曼原虫SSUrDNA序列大小均为 392bp ;序列差异均发生在两个独特序列区 (UQ Ⅰ和UQ Ⅱ ) ;山丘疫区L .d甘肃分离株和四川分离株均在UQ Ⅱ区上有 2个相同的碱基突变 ,L .d甘肃分离株UQ Ⅰ区上有 1个碱基突变 ;无移码突变。 结论 ]山丘疫区分离株与平原疫区分离株之间的碱基序列有差异 ,平原疫区L .d山东分离株与婴儿利什曼原虫 (L .infantum)的碱基序列相同

SEQUENCE ANALYSIS OF SSU rDNA VARIABLE REGIONS OF LEISHMANIAISOLATES FROM HILLY FOCI AND PLAIN FOCI OF CHINA

OBJECTIVE: To analyze the sequence difference of the SSU rDNA variable regions of Leishmania isolates from hilly foci and plain foci of China. METHODS: Specific SSU rDNA fragments from nuclear DNA of five Leishmania species and isolates were amplified by PCR. The amplified DNA fragments were cloned into pGEMR-T Easy vector. The specific fragments were sequenced by the automated DNA sequencer. RESULTS: Sequence analysis showed that the amplified DNA fragments of five Leishmania species and isolates were all 392 bp in length, point mutations were located in the two unique sequence (UQ-I and UQ-II); L. d. SC10 and L. d. GS7 had two same point mutations in UQ-II, only L. d. GS7 had one in UQ-I; no insertion/deletion. CONCLUSION: Sequence difference of the SSU rDNA variable region existed between Leishmania isolates from hilly foci and plain foci; The sequences of the SSU rDNA variable regions of L. d. SD2 isolate and L. infantum were identical.