Zhai Lijie, Dai Xing, Meng Jihong
Department of Microbiology and Immunology, School of Medicine, Southeast University, 87# Dingjiaqiao Rd., Nanjing, Jiangsu 210009, China.
Virus Res. 2006 Sep;120(1-2):57-69. doi: 10.1016/j.virusres.2006.01.013. Epub 2006 Feb 10.
Some genomic regions for hepatitis E virus (HEV) genotyping have been reported to correlate well with the results from the phylogenetic analyses on the basis of the complete genome. However, few studies have systemically investigated the genomic regions for HEV genotyping using a combined phylogenetic and statistical approach. A consensus region for HEV genotyping has not been determined. In this study the nucleotide identities and genetic distances of 24 partial genomic regions and the complete genome sequences of 37 HEV strains were compared statistically. It was demonstrated with both one-way ANOVA and two-way ANOVA that only one genomic region in RNA-dependent RNA polymerase domain (4254-4560nt) for which there were no significant differences when compared with the full-length genome (P>0.05). The same four genotypes were identified by phylogenetic analysis based on this statistically predicted region identified as for the complete genome. RT-PCR amplification of HEV strains from all four genotypes confirmed conservation of the flanking primer sites of this region. Serum samples from 20 patients with a clinical diagnosis of hepatitis E were further analyzed by PCR using the same primers, 13 were positive and could be classified into genotype 4. These data strongly suggested that this newly identified region could be used for future HEV genotyping.
据报道，一些用于戊型肝炎病毒（HEV）基因分型的基因组区域与基于全基因组的系统发育分析结果具有很好的相关性。然而，很少有研究使用系统发育和统计相结合的方法对HEV基因分型的基因组区域进行系统研究。尚未确定用于HEV基因分型的共有区域。在本研究中，对37株HEV菌株的24个部分基因组区域和全基因组序列的核苷酸同一性和遗传距离进行了统计学比较。单因素方差分析和双因素方差分析均表明，在RNA依赖的RNA聚合酶结构域中只有一个基因组区域（4254 - 4560nt），与全长基因组相比无显著差异（P>0.05）。基于这个经统计学预测的区域进行系统发育分析，所鉴定出的基因型与基于全基因组所鉴定出的基因型相同。对来自所有四种基因型的HEV菌株进行RT-PCR扩增，证实了该区域侧翼引物位点的保守性。使用相同引物通过PCR进一步分析了20例临床诊断为戊型肝炎的患者的血清样本，其中13例呈阳性，可归类为基因型4。这些数据强烈表明，这个新鉴定出的区域可用于未来的HEV基因分型。
