title: [Relationship between hepatitis B virus genotypes and basic core promoter/precore mutations in patients with severe hepatitis.].
abstract: BACKGROUND
  To investigate the relationship between hepatitis B virus genotypes and basic core promoter (BCP)/precore mutations in patients with severe hepatitis.
  
  
  METHODS
  HBV genotypes were determined by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) in 52 patients with severe hepatitis and 52 cases with chronic hepatitis B (CHB). Eight samples of genotypes B and C were randomly selected and their S gene was directly sequenced, and then their phylogenetic trees were analyzed. Fifteen samples of each of genotypes B and C were randomly selected and their BCP and precore genes were directly sequenced with PCR, and then the relationship between genotypes and BCP(T1762/A1764)/precore (A1896) mutations were analyzed.
  
  
  RESULTS
  Genotype B C and mixed genotypes (B and C) were detected in patients with severe hepatitis in Quanzhou area. Genotype B was the majority with a proportion 48.08% others had a proportion 30.77% and 17.31%, respectively. Genotype A, E and F were not detected. The percents of genotype C, mixed B and C in severe hepatitis were significantly higher than that in CHB. The double mutation in BCP (T1762/A1764) was significantly more frequent in severe hepatitis with genotype C than that in genotype B (P less than 0.05). However, there was no significant difference in the distribution of precore mutant with A1896 between genotype B and C patients (P greater than 0.05).
  
  
  CONCLUSIONS
  Genotype C may induce more severe liver inflammation than that genotype B may do. Mixed genotypes B and C infection may be an important determinant of inducing severe hepatitis. The double mutation in BCP (T1762/A1764) was more common in severe hepatitis with genotype C than that with genotype B.
authors.affiliation: Clinical Liver Diseases Research Center of Nanjing Military Command, The No.180 Hospital of The People's Liberation Army, Quanzhou 362000, China. Corresponding author: XU Zheng-ju, E-mail: h180@163.com.
authors.forename: Z J
authors.initials: ZJ
authors.lastname: Xu
authors.forename: H
authors.initials: H
authors.lastname: Yang
authors.forename: X L
authors.initials: XL
authors.lastname: Chen
authors.forename: J K
authors.initials: JK
authors.lastname: Shen
authors.forename: Q H
authors.initials: QH
authors.lastname: Zhang
authors.forename: C G
authors.initials: CG
authors.lastname: Wang
mesh_terms: D005838:Genotype; D006515:Hepatitis B virus / Q000235:genetics; D019694:Hepatitis B, Chronic / Q000821:virology; D006801:Humans; D009154:Mutation; D010802:Phylogeny