title: Rate of YMDD motif mutants in lamivudine-untreated Iranian patients with chronic hepatitis B virus infection.
abstract: BACKGROUND
  Lamivudine is used for the treatment of chronic hepatitis B patients. Recent studies show that the YMDD motif mutants (resistant hepatitis B virus) occur as natural genome variability in lamivudine-untreated chronic hepatitis B patients. In this study we aimed to determine the rate of YMDD motif mutants in lamivudine-untreated chronic hepatitis B patients in Iran.
  
  
  METHODS
  A total of 77 chronic hepatitis B patients who had not been treated with lamivudine were included in the study. Serum samples from patients were tested by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) for detection of YMDD motif mutants. All patients were also tested for liver enzymes, anti-HCV, HBeAg, and anti-HBe.
  
  
  RESULTS
  Of the 77 patients enrolled in the study, 73% were male and 27% were female. Mean ALT and AST levels were 124.4+/-73.4 and 103.1+/-81 IU/l, respectively. HBeAg was positive in 40% and anti-HBe in 60% of the patients. Anti-HCV was negative in all of them. YMDD motif mutants were not detected in any of the patients despite the liver enzyme levels and the presence of HBeAg or anti-HBe.
  
  
  CONCLUSIONS
  Although the natural occurrence of YMDD motif mutants in lamivudine-untreated patients with chronic hepatitis B has been reported, these mutants were not detected in Iranian lamivudine-untreated chronic hepatitis B patients.
authors.affiliation: Clinical Research Department, Pasteur Institute of Iran, No. 69, Pasteur Ave., Tehran, Iran.
authors.forename: Amitis
authors.initials: A
authors.lastname: Ramezani
authors.forename: Ali Akbar
authors.initials: AA
authors.lastname: Velayati
authors.forename: Mohammad Reza Hasanjani
authors.initials: MR
authors.lastname: Roshan
authors.forename: Latif
authors.initials: L
authors.lastname: Gachkar
authors.forename: Mohammad
authors.initials: M
authors.lastname: Banifazl
authors.forename: Hossein
authors.initials: H
authors.lastname: Keyvani
authors.forename: Arezoo
authors.initials: A
authors.lastname: Aghakhani
mesh_terms: D000293:Adolescent; D000328:Adult; D020816:Amino Acid Motifs / Q000235:genetics*; D002648:Child; D005260:Female; D006515:Hepatitis B virus / Q000235:genetics*; D019694:Hepatitis B, Chronic / Q000188:drug therapy* / Q000453:epidemiology / Q000821:virology; D006801:Humans; D007492:Iran / Q000453:epidemiology; D019259:Lamivudine / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D018894:Reverse Transcriptase Inhibitors / Q000627:therapeutic use*
chemical_list: D018894:Reverse Transcriptase Inhibitors; D019259:Lamivudine