Hepatitis B e antigen in sera from individuals infected with hepatitis B virus of genotype G.
Hepatitis B virus (HBV) genotype G (HBV/G) was detected in sera from four individuals by polymerase chain reaction with hemi-nested primers deduced from an insertion of 36 nt in the core gene that is specific for this genotype. Despite two stop codons in the precore region characteristic of HBV/G, all patients were positive for hepatitis B e antigen (HBeAg) in serum. When 10 HBV clones were propagated from one patient, and sequenced within precore region and a section of the core gene, 6 clones were HBV/G while 2 were genotype A (HBV/A); a recombination between HBV/G and HBV/A occurred in the remaining 2 clones. Mixed infection of HBV/G and HBV/A, as well as the recombination, was demonstrated in the sequence of preS1 and preS2 regions also. Coinfection with HBV/G and HBV/A was demonstrated in the other three patients, and their recombination in two patients. Ten HBV clones were propagated from one patient at two time points separated by 1 year. Clones of HBV/A, HBV/G and their recombination were found in 9 : 1 : 0 when the patient was positive for HBeAg, while the proportion shifted to 0 : 8 : 2 after the patient seroconverted to anti-HBe. In conclusion, HBV/G is frequently found as a coinfection with HBV/A. This coinfection would explain the presence of HBeAg in individuals infected with HBV/G. Along with seroconversion to anti-HBe, HBV/G would be selected accompanied by the recombination with HBV/A. Further studies should be performed to confirm these findings.
Kato
Hideaki
H
Second Department of Medicine, Nagoya City University Medical School, Nagoya, Japan.
Orito
Etsuro
E
Gish
Robert G
RG
Bzowej
Natalie
N
Newsom
Margaret
M
Sugauchi
Fuminaka
F
Suzuki
Seiji
S
Ueda
Ryuzo
R
Miyakawa
Yuzo
Y
Mizokami
Masashi
M
D000328:Adult; D000595:Amino Acid Sequence / Q000235:genetics; D001483:Base Sequence / Q000235:genetics; D004279:DNA, Viral / Q000235:genetics; D005838:Genotype; D006509:Hepatitis B / Q000276:immunology*; D006513:Hepatitis B e Antigens / Q000097:blood*; D006515:Hepatitis B virus / Q000235:genetics*; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D010802:Phylogeny
D004279:DNA, Viral; D006513:Hepatitis B e Antigens