Full-Length Sequences of Six Hepatitis E Virus Isolates of Genotypes III and IV from Patients with Sporadic Acute or Fulminant Hepatitis in Japan

Abstract

Objective: Ranges of variation and conservation in sequence need to be defined for detecting and genotyping hepatitis E virus (HEV). Methods: Six HEV isolates from Japanese patients were sequenced over the entire genome and compared phylogenetically along with 16 reported HEV isolates, including two from pigs. Results: Three of the six HEV isolates were of genotype III, and the remaining three were of genotype IV. Local clusterings of Japanese HEV isolates were observed in the phylogenetic analyses, including a swine HEV isolate reported previously (swJ570). All six HEV isolates possessed three open reading frames (ORFs). The ORF3 in the three isolates of genotype III were in a different reading frame, while that in the three isolates of genotype IV were in the same reading frame as ORF1. A stretch of 46–96 nucleotides was identified, point mutations and deletions in which were specific for the four genotypes (I–IV). A polymerase chain reaction method was developed with 9 nested universal primers, deduced from conserved regions in the 5′-terminal sequences of the 22 HEV genomes. Conclusions: Conserved and genotype-specific variation in HEV sequences, identified in the comparison of 22 full-length genomes, would be useful in designing primers for sensitive detection and specific genotyping of HEV RNA.

Characterization of Two Novel Linear B-Cell Epitopes in the Capsid Protein of Avian Hepatitis E Virus (HEV) That Are Common to Avian, Swine, and Human HEVs

“…epatitis E is usually an acute and self-limiting disease in humans, is an epidemic in many developing countries in Asia and Africa (1)(2)(3), and occurs sporadically in some industrialized countries (4)(5)(6). The causative agent, hepatitis E virus (HEV), belongs to the Hepeviridae family and is a single-stranded, positivesense RNA virus.…”

Prevalence of Hepatitis E Virus (HEV) Infection in Wild Boars (Sus scrofa leucomystax) and Pigs in Gunma Prefecture, Japan

“…The HEV infections in Asia and Africa are mainly caused by G I, and the majority of the GII infection have been reported in Mexico and Nigeria. On the other hand, only a single case of infection with GIII or GIV has been described in the United States, European counties, Argentina, Taiwan and China [17,21,22]. In Japan, most imported cases with G I have derived from epidemic areas such as Asia and Africa [2]; however, G III or G IV has also been detected in acute hepatitis patients who have never traveled to HEV epidemic areas [6,8,13,14,20,21,24,29].…”

Full-Length Sequences of Two Hepatitis E Virus Isolates Representing an Eastern China-Indigenous Subgroup of Genotype 4

“…Detection of Serum HEV-RNA HEV-RNA was detected in the sera using the reverse transcription (RT)-polymerase chain reaction (PCR) system according to the previously reported methods [14] . Briefly, nucleic acids were extracted from 50 l of serum with an extraction kit (SMI-TEST EX-R&D, Genome Science Laboratories, Fukushima, Japan).…”

“…Full-length sequences of the HEV isolates were determined according to Takahashi et al [14] with some modifications. Briefly, nucleic acids extracted from the sera were subjected to RT-PCR in 17 overlapping regions with 20-mer primers designed based on the nucleotide sequences of various HEV isolates deposited in the DDBJ/GeneBank/EMBL databases.…”