上海及新疆地区猪戊型肝炎病毒开放阅读码框架2序列的克隆与分析

CLONING AND SEQUENCE ANALYSIS OF OPEN READING FRAME 2 OF SWINE HEPATITIS E VIRUSES FROM SHANGHAI AND XINJIANG AREAS

通过已建立的动物戊型肝炎病毒（Hepatitis E virus,HEV）RT-nPCR方法,检测上海地区和新疆地区猪群样品。扩增HEV开放读码框架2（open reading frame 2,ORF2）保守区,产物为507 bp。经克隆、测序,获得20株上海株、3株新疆株序列,采用分子生物学软件与47株已知HEV进行同源性、进化关系分析。结果23株序列从同源性比对和进化关系分析均属HEVⅣ型,上海株间507 bp的核苷酸同源性为94.1%~100.0%,与上海猪源（DQ450072）、日本人源Japan1（AB369690）亲缘关系近;3株新疆株507 bp间的核苷酸同源性为86.1%~98.2%,与新疆猪源China SW1（AY594199）、中国人源T1株（AJ272108）亲缘关系近;上海株与新疆株间的核苷酸同源性为82.6%~100.0%,提示上海株与新疆株间存在差异。23株HEV在时间和地域关系分析,提示不同年份的新疆株存在差异,同年份不同猪场的新疆株进化关系存在差异,不同年份、不同区县的上海株进化关系也存在差异。

A total of twenty three Hepatitis E viruses（HEV） were detected in swine samples from Shanghai and Xinjiang areas by using reverse transcription nested polymerase chain reaction（RT-nPCR）.The open reading frame（ORF） 2 conservation region of these viruses was amplified to be 507 bp in length and then cloned and sequenced.Phylogenetic analysis of these strains and other 47 known HEV strains was performed to determine their relatedness.The results showed that all HEV strains from Shanghai and Xinjiang belonged to the genotype IV.Twenty Shanghai strains shared 94.1%-100% homology and were closely related with Shanghai swine strain and Japan human strain.Similarly,3 Xinjiang strains shared 86.1%-98.2% homology and were close to Xinjiang swine strain and human strain.There was 82.6%-100% homology between Shanghai and Xinjiang strains,which implicated genetic differences existing among Shanghai and Xinjiang strains.