两株猪HEV病毒株全基因组序列分析  

The analysis of the complete genome sequence of two swine hepatitis E virus strains isolated from Xin- jiang

作　　者：付红伟杨桂芳李昕 

机构地区：[1]天津医科大学总医院医学检验科,300052

出　　处：《实用检验医师杂志》2012年第2期84-91,共8页Chinese Journal of Clinical Pathologist

摘　　要：目的测定两株从新疆地区分离的猪戊型肝炎（hepatitis E，HEV）病毒株全基因组序列，并在全基因组水平上分析猪HEV病毒株与人源HEV的关系。方法设计HEV基因4型通用PCR引物，用巢式反转录聚合酶链反应法（reverse—transcription—nested polymerase chain reaction，RT—nPCR）分段扩增猪HEV病毒株CHN—XJ—SW13和CHN—XJ—SW33的全基因组序列；用cDNA末端快速扩增法（rapid amplification of cDNA，RACE）扩增其末端序列；对扩增的目的片段进行克隆测序，并对拼接后的基因组进行序列比对和进化分析。结果除3＇polyA尾外，CHN—XJ—SW13和CHN—XJ—SW33基因组全长分别为7241bp和7238bp，两病毒株均与基因4型HEV核苷酸同源性最高，为82．8％～95．5％；与基冈1～3型HEV核苷酸同源型仅为72．1％-74．9％。CHN—XJ—SW13与分离自湖南、上海的猪HEV病毒株（HC10—44，HC1—88，estw2，ch—shsw1和SWXJ03）共同组成新的HEV基因亚型：4n亚型，且该病毒株与香港人HEV（HK104—2004）在ORF1部分核苷酸序列同源性高达94．6％。基因进化分析显示CHN—XJ—sw33属于HEV4a亚型，在全基因组水平上与JKO—ChiSai98C核苷酸同源性高达95．5％。结论本文研究成功完成了两株猪HEV病毒株全基因组序列的鉴定，其中CHN—XJ—SW13为我国本土的HEV新培因亚型；在全基因组水平上猪HEV与人HEV高度同源的特性为基因4型HEV从猪到人传播的可能提供了更可靠的证据。Objective To determine the complete genome of swine hepatitis E （HEV） isolated from Xinjiang, China, and to analyzed the correlation between swine HEV and human HEV. Methods The PCR universal primer of HEV genotype 4 were designed. The complete genome sequence of HEV isolates CHN-XJ- SW13 and CHN-XJ-SW33 were amplified with reverse-transcription-nested polymerase chain reaction （RT- nPCR ） and 5＂ and 3＂ ends of viral genome were amplified with rapid amplification of cDNA ends （RACE）. The PCR products were cloned and sequenced. The sequence and phylogenetic analysis of the two swine HEV iso- lates were performed. Results The full genome of CHN-XJ-SWI 3 and CHN-XJ-SW33 strains consisted of 7241 bp and 7238 bp nucleotides excluding the polyA tail, respectively. The full-genomic sequencing showed that the CHN-XJ-SW13 and CHN-XJ-SW33 strains shared similarity with all known HEV genotype 1,2 and 3 isolates by 72.1%-74.9% and with an identity of 82.8%-95.5% among genotype 4 HEV isolates. CHN-XJ- SW13 isolate has formed a new sub-group （4n） with other swine HEV strains （HC10-44, HC1-88, estw2, ch-shswl and SWXJ03） isolated form Hunan Province and Shanghai. The partial ORF1 sequencing （145- 423nt） showed that CHN-XJ-SW13 shared a high nucleotide identity of 94.6% with the HongKong human strain HK104-2004. CHN-XJ-SW33 shared a high nucleotide identity of 95.5% with JKO-ChiSai98C and lo- cated in the branch of HEV subtype 4a. Conclusion The full-genomic sequencing of two HEV strains are i- dentified successfully, and CHN-XJ-SW13 is a new sub-group in our country. A high identity of nucleotide sequences between human and swine HEV strains isolated in Xinjiang suggested the possibility of swine to hu- man transmission of sporadic HEV in HEV-endemic regions.

关 键 词：戊型肝炎病毒 猪 HEV基因分型 HEV基因哑型 

分 类 号：R373.21[医药卫生—病原生物学]