title: [Subgenotype and serotype analysis of hepatitis B virus in Korean chronic hepatitis B patients under treatment].
abstract: BACKGROUND
  Hepatitis B virus (HBV) detected in Korean patients almost belongs to genotype C, which is subdivided into subgenotype C1 (or Cs) and C2 (or Ce). It was recently reported that the risk of hepatocellular carcinoma is different between subgenotype C1 and C2. Thus, we studied the distribution of subgenotypes of HBV in Korean chronic hepatitis B (CHB) patients.
  
  
  METHODS
  Specimens of 421 patients, who were diagnosed as CHB and underwent antiviral treatment, were used. After sequence analysis for HBV S gene, subgenotype was identified through phylogenetic analysis. Utilizing the same sequence data, the distribution of serotypes was also investigated.
  
  
  RESULTS
  Among 421 patient specimens, genotype C was found in 419 (99.5%) and genotype B in 2 (0.5%). Among the genotype C strains, 417 strains were C2 subgenotype and 2 strains were mixed subgenotypes. However, C2 was evidently found even in the mixed sequences. Serotypes of 419 HBV with genotype C were classified as follows: adr, 385 (91.9%), adw, 22 (5.3%), ayr, 2 (0.4%) and mixed serotype, 10 (2.3%). Serotype of both HBV with genotype B was adw.
  
  
  CONCLUSIONS
  It was found that HBV detected in Korean CHB patients under treatment almost all belong to the C2 (Ce) genotype.
authors.affiliation: Department of Laboratory Medicine, University of Ulsan College of Medicine, Gangneung Asan Hospital, Gangneung, Korea.
authors.forename: Choong-Hwan
authors.initials: CH
authors.lastname: Cha
authors.forename: Yong-Hak
authors.initials: YH
authors.lastname: Sohn
authors.forename: Sun-Young
authors.initials: SY
authors.lastname: Ko
authors.forename: Heung-Bum
authors.initials: HB
authors.lastname: Oh
mesh_terms: D000998:Antiviral Agents / Q000627:therapeutic use; D001800:Blood Specimen Collection; D005838:Genotype; D006515:Hepatitis B virus / Q000145:classification* / Q000235:genetics; D019694:Hepatitis B, Chronic / Q000175:diagnosis / Q000188:drug therapy / Q000821:virology*; D006801:Humans; D007723:Korea; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D012703:Serotyping
chemical_list: D000998:Antiviral Agents