title: [Detection of mutants of the "a" determinant region of hepatitis B surface antigen S gene among Wuhan childhood patients].
abstract: OBJECTIVE
  To investigate whether the presence of HBV mutant in vaccinees simply reflects the prevalence of HBV mutant in a specific geographic area or is indeed due to the immune pressure induced by vaccination.
  
  
  METHODS
  HBV S genes were amplified by using polymerase chain reaction (PCR) and DNA sequence analysis of the "a" determinant was performed on sera from 30 childhood patients with immunoprophylaxis and 30 patients without vaccinations.
  
  
  RESULTS
  Mutations of the "a" determinant were detected in 8 of the 60 patients. They were all of the adw subtype. The prevalence of amino acid substitutions as detected by direct sequencing was higher in those fully-vaccinated than of those not vaccinated. In all 8 vaccinated and also with detectable mutants, the mean age was older than the other vaccinated children.
  
  
  CONCLUSIONS
  The prevalence of mutants is related to HBV subtypes and genotypes. Universal vaccination has accelerated an accumulation of HBsAg "a" determinant mutants with amino acid changes critical for immune escape in vaccinated children who became carriers. This suggests that new vaccination strategies should be considered.
authors.affiliation: Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
authors.forename: Quan
authors.initials: Q
authors.lastname: Hu
authors.forename: Jian-guo
authors.initials: JG
authors.lastname: Huang
authors.forename: Yan-chang
authors.initials: YC
authors.lastname: Lei
authors.forename: Hong-ping
authors.initials: HP
authors.lastname: Huang
authors.forename: Yan
authors.initials: Y
authors.lastname: Yang
authors.forename: Dong-liang
authors.initials: DL
authors.lastname: Yang
mesh_terms: D002648:Child; D002681:China; D000939:Epitopes / Q000235:genetics*; D005260:Female; D006509:Hepatitis B / Q000517:prevention & control; D006514:Hepatitis B Surface Antigens / Q000235:genetics*; D017325:Hepatitis B Vaccines / Q000276:immunology*; D006515:Hepatitis B virus / Q000235:genetics; D006801:Humans; D008297:Male; D017354:Point Mutation; D014611:Vaccination
chemical_list: D000939:Epitopes; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines