title: Hepatitis B virus genotype G is an extremely rare genotype in Japan.
abstract: BACKGROUND:: Hepatitis B virus (HBV) has been classified into seven genotypes (A-G). HBV genotypes have a geographically characteristic distribution. Since HBV genotype G (HBV/G) was identified recently, little is known about the distribution of HBV/G in Japan. The aim of this study was to clarify this issue. PATIENTS AND METHODS:: Seven hundred and twenty-one serum samples obtained from patients with HBV in Japan were investigated. The patients included 149 asymptomatic carriers, 325 with chronic hepatitis, 129 with liver cirrhosis, and 118 with hepatocellular carcinoma. Six HBV genotypes (A-F) were determined by restriction fragment length polymorphim targeting to the S region of the HBV genome. Furthermore, HBV/G was investigated by polymerase chain reaction with hemi-nested primers derived from an HBV/G-specific nucleotide sequence. RESULTS:: Of the 721 serum samples investigated, 12 subjects were classified as having HBV/A, 88 HBV/B, 610 HBV/C, 3 HBV/D, and 1 HBV/F. Seven subjects had a mixed infection with distinct genotypes, two with HBV/A and HBV/D, and five with HBV/B and HBV/C. HBV/G was not identified among the 721 samples. CONCLUSION:: HBV/G was not identified in a large cohort of patients with HBV, either single or dual infection. HBV/G seems to be an extremely rare genotype in Japan.
authors.affiliation: Department of Clinical Molecular Informative Medicine, Nagoya City University, Graduate School of Medical Sciences, Kawasumi 1, Mizuho-ku, Mizuho-cho, Nagoya 467-8601, Japan; Department of Internal Medicine and Molecular Science, Nagoya City University, Graduate School of Medical Sciences, Nagoya, Japan.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Kato
authors.forename: Fuminaka
authors.initials: F
authors.lastname: Sugauchi
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ozasa
authors.forename: Takanobu
authors.initials: T
authors.lastname: Kato
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sakugawa
authors.forename: Michio
authors.initials: M
authors.lastname: Sata
authors.forename: Keisuke
authors.initials: K
authors.lastname: Hino
authors.forename: Morikazu
authors.initials: M
authors.lastname: Onji
authors.forename: Takeshi
authors.initials: T
authors.lastname: Okanoue
authors.forename: Eiji
authors.initials: E
authors.lastname: Tanaka
authors.forename: Sumio
authors.initials: S
authors.lastname: Kawata
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Suzuki
authors.forename: Shuhei
authors.initials: S
authors.lastname: Hige
authors.forename: Tomoyoshi
authors.initials: T
authors.lastname: Ohno
authors.forename: Etsuro
authors.initials: E
authors.lastname: Orito
authors.forename: Ryuzo
authors.initials: R
authors.lastname: Ueda
authors.forename: Masashi
authors.initials: M
authors.lastname: Mizokami