2007年吉林省散发野型麻疹病毒H基因序列分析

目的分析2007年吉林省散发野型麻疹病毒的基因型别和特征。方法对2007年吉林省分离到的3株散发麻疹野型病毒,经RT-PCR扩增血凝素(H)基因片段,克隆到pMD19-T载体,进行酶切鉴定及序列测定,并分析核苷酸序列,与GenBank中麻疹病毒的22个代表株H基因序列的同源性进行比较。结果RT-PCR产物经琼脂糖凝胶电泳,可见大小约为570bp的片段,克隆至pMD19-T载体后,酶切鉴定结果与预期相符。3株麻疹病毒均属H1基因型,其H基因之间同源性为98.5%～99.6%,与其他已知麻疹病毒的22个基因代表株相比,在核苷酸水平上最大变异为9.7%。3株病毒与H1a参考株Chin93-2、H1b参考株Chin94-5和H1c参考株Chin94-7的平均遗传距离分别为0.007～0.015、0.013～0.021和0.015～0.023。结论H1a基因型毒株是导致吉林省2007年春季麻疹散发的优势毒株。

Sequencing of Hemagglutinin Gene of Wild-type Measles Virus Causing Sporadic Cases in Jilin Province, China

Objective To analyze the genetic characteristics and genotype of wild-type measles virus strains isolated in Jilin Province,China in 2007.Methods Isolate 3 measles virus strains from patients for amplification of hemagglutinin (H) gene fragment by RT-PCR.Clone the amplified H gene fragment to pMD19-T vector for sequencing and analysis of homology to those of 22 wild-type strains reported in GenBank.Results The gene fragment at a length of about 570 bp was amplified by RT-PCR.The result of restriction analysis of the amplified gene was consistent with that expected.All the 3 isolated virus strains were of genotype H1.The homololgy of H gene of the 3 strains was 98.5%～99.6%.Compared with those of the 22 wild-type viruses in GenBank,the variation of nucleotides of the 3 isolated strains was up to 9.7%.The mean genetic distances of the 3 isolated strains to H1a reference strain Chin93-2,H1b reference strain Chin94-5 and H1c reference strain Chin94-7 were 0.007～0.015,0.013～0.021 and 0.015～0.023 respectively.Conclusion The wild-type measles virus of genotype H1a might be the dominant strain causing sporadic cases in Jilin Province in spring 2007.