[Partial nucleotide sequences of hepatitis E viruses isolated from patients in 14 cities of China].

OBJECTIVE

To investigate the genotypes of hepatitis E viruses isolated in China.

METHODS

The partial genome of open reading frame 2 (nt6461-6860, nt5994-6294) of 45 HEV isolated from patients in 14 cities of China was amplified and sequenced using polymerase chain reaction and direct sequencing.

RESULTS

41 of 45 isolates (91%) shared the same genotype with HEV Burma strain (B), with nucleotide identities higher than 98% with the representative HEV Chinese strain. Only 4 HEV isolates were significantly divergent from the 3 prototype strains of HEV, with nucleotide identities of 77%-80% with HEV Burmese/Chinese strain, 74%-76% with Mexico strain and 74%-77% with the newly discovered HEV US/Swine strain, respectively. Phylogenetic analysis suggested that these 4 isolates represented 2 different subtypes belonging to a novel genotype of HEV, which was significantly divergent from the prototype Mexican, Burmese and US/Swine isolates.

CONCLUSION

Among patients with hepatitis E in China, most are infected with the Chinese prototype HEV, and only a small part with the new genotype HEV.