长春地区人与猪戊型肝炎病毒分子流行病学及部分基因序列分析

Partial nucleotide sequencing and molecular epidemiology of hepatitis E viruses from swine and patients with hepatitis E infection in Changchun of Jilin province

目的 分析长春地区猪和人群流行的戊型肝炎病毒的系统进化关系。方法 参照文献设计引物．对长春地区猪和人群流行的8株HEV（其中3株来源于人，5株来源于猪）进行RT-PCR，并将RT-PCR产物克隆到PMD18-T载体。筛选阳性重组质粒测序，测序结果采用Clustal X v．1．8进行多重比对分析，并与基因1～4型HEV代表株的核苷酸及氨基酸进行同源性比较。绘制遗传进化树。结果 本研究获得的8株HEV核苷酸同源性在91．2％～99．1％。推导氨基酸同源性在97．4％～100％之间；基因1～4型内各株序列间同源性分别为：87．9％～100％,100％，85．9％～96．6％。84．8％～100％。结论 研究表明获得的长春各株病毒均属基因4型。由进化关系看长春地区猪HEV与人HEV可能由同一毒株进化而来。

In order to analyze the phylogenetic relationship of hepatitis E virus （HEV）infections between humans and swine, the HEV-RNA was determined by using RT-PCR, and the RT-PCR products was then cloned into vector pMD18-T, and then sequenced, the sequences of genotypes I-IV were employed for analysis. Using clustal X v＇l. 81＇multiple alignments of nucleotides and amino acid sequences were carried out, and thus the phylogenetic tree was established, In the present study, the HEV gene fragments of 8 viral isolates were successfully cloned with the nucleotide homologies of 91.25-99.1% and the puta- tive amino acid homologies of 97.4%- 100%. The sequence homologies among genotypes I-V were 87.9%- 100% , 100%, 85.9 %- 96.6 % ,84.8%-100% respectively. It is evident that the HEV strains isolated in Changchun of Jilin province belong to genotypes IV and they may be evolved from the same ancerstor.