title: Lamivudine resistance mutations in patients infected with hepatitis B virus genotype D.
abstract: OBJECTIVE
  To determine the distribution of viral genotypes for primary or acquired lamivudine resistance.
  
  
  METHODS
  A total of 283 patients with chronic hepatitis B virus (HBV) infection (245 patients with chronic hepatitis B and 38 inactive hepatitis B surface antigen carriers) were included in the study. The HBV genotype was determined by using quantitative real-time polymerase chain reaction and sequence analysis, and tyrosine-methionine-aspartate-aspartate (YMDD) motif mutations were determined using the reverse transcriptase hybridization method.
  
  
  RESULTS
  Lamivudine resistance was determined in a total of 25 (10.7%) chronic hepatitis B patients. Eight subjects (4%) had primary resistance to lamivudine, and 17 (53.1%) had secondary resistance to lamivudine. Genotype D, which was isolated from 267 of the patients with chronic HBV infection, was the dominant genotype in Turkey.
  
  
  CONCLUSIONS
  Identification of YMDD motif mutations should have a positive impact on the selection of proper antiviral medication for patients, even for those who are nucleoside naïve.
authors.affiliation: Department of Infectious Diseases and Clinical Microbiology, Medical School of Erciyes University, 38039 Kayseri, Turkey. oyildiz@erciyes.edu.tr
authors.forename: Orhan
authors.initials: O
authors.lastname: Yıldız
authors.forename: Bilgehan
authors.initials: B
authors.lastname: Aygen
authors.forename: Nese
authors.initials: N
authors.lastname: Demirtürk
authors.forename: Tuna
authors.initials: T
authors.lastname: Demirdal
authors.forename: Dilara
authors.initials: D
authors.lastname: Inan
authors.forename: Taner
authors.initials: T
authors.lastname: Yıldırmak
authors.forename: Arzu
authors.initials: A
authors.lastname: Kantürk
authors.forename: Ediz
authors.initials: E
authors.lastname: Tütüncü
mesh_terms: D000328:Adult; D000368:Aged; D024882:Drug Resistance, Viral / Q000235:genetics*; D005260:Female; D005838:Genotype; D006515:Hepatitis B virus / Q000187:drug effects / Q000235:genetics*; D019694:Hepatitis B, Chronic / Q000188:drug therapy* / Q000235:genetics*; D006801:Humans; D019259:Lamivudine / Q000494:pharmacology / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D060888:Real-Time Polymerase Chain Reaction; D018894:Reverse Transcriptase Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D055815:Young Adult
chemical_list: D018894:Reverse Transcriptase Inhibitors; D019259:Lamivudine