title: Mutation in HBV RNA-dependent DNA polymerase confers resistance to lamivudine in vivo.
abstract: The (-) enantiomer of 3'-thiacytidine (lamivudine) has been found to be a potent inhibitor of hepatitis B virus (HBV) and human immunodeficiency virus (HIV) replication. Mutation of methionine to valine or isoleucine at the YMDD (tyrosine, methionine, aspartate, aspartate) motif of the HIV reverse transcriptase has been shown to be responsible for lamivudine resistance in HIV. The hepadnaviruses also have the YMDD motif in their DNA polymerase. Therefore, it is possible that hepadnaviruses could develop lamivudine resistance by a similar mutation at this motif. We analyzed the HBV from a liver transplantation patient who developed recurrent HBV viremia during lamivudine treatment. The polymerase gene was amplified by polymerase chain reaction (PCR), and the region coding for the YMDD motif was sequenced. The pretreatment HBV sequence coded for YMDD, while the lamivudine-resistant mutant HBV coded for YIDD (tyrosine, isoleucine, aspartate, aspartate). With the documented changes in the YMDD motif of lamivudine-resistant HIV, it is likely that the methionine-to-isoleucine mutation in the YMDD motif of the HBV polymerase contributes significantly to the lamivudine-resistance of HBV isolated from this patient.
authors.affiliation: Department of Medical Microbiology and Immunology, Glaxo Wellcome-Heritage Research Institute, University of Alberta, Edmonton, Canada.
authors.forename: G A
authors.initials: GA
authors.lastname: Tipples
authors.forename: M M
authors.initials: MM
authors.lastname: Ma
authors.forename: K P
authors.initials: KP
authors.lastname: Fischer
authors.forename: V G
authors.initials: VG
authors.lastname: Bain
authors.forename: N M
authors.initials: NM
authors.lastname: Kneteman
authors.forename: D L
authors.initials: DL
authors.lastname: Tyrrell
mesh_terms: D000328:Adult; D000998:Antiviral Agents / Q000627:therapeutic use*; D001483:Base Sequence; D017124:Conserved Sequence; D004259:DNA-Directed DNA Polymerase / Q000235:genetics*; D004352:Drug Resistance, Microbial / Q000235:genetics; D005260:Female; D006509:Hepatitis B / Q000097:blood / Q000821:virology; D006515:Hepatitis B virus / Q000235:genetics*; D006801:Humans; D019259:Lamivudine / Q000627:therapeutic use*; D015335:Molecular Probes / Q000235:genetics; D008969:Molecular Sequence Data; D009154:Mutation; D011183:Postoperative Complications; D012367:RNA, Viral / Q000235:genetics*; D012008:Recurrence; D014766:Viremia / Q000209:etiology
chemical_list: D000998:Antiviral Agents; D015335:Molecular Probes; D012367:RNA, Viral; D019259:Lamivudine; D004259:DNA-Directed DNA Polymerase