title: Persistence of azidothymidine-resistant human immunodeficiency virus type 1 RNA genotypes in posttreatment sera.
abstract: The rate of reversion from azidothymidine (zidovudine; AZT) resistance was studied by direct sequencing of human immunodeficiency virus type 1 (HIV-1) virion RNA in sera from four patients who discontinued long-term treatment. Before cessation of treatment, all four patients harbored HIV-1 with multiple mutations reported to confer AZT resistance. In three patients, slow reversions of these mutations starting after 9, 9, and 18 months were detected. The slow reversions indicate that AZT-resistant HIV-1 variants are likely to have an unaltered replicative capacity and pathogenic potential. Furthermore, there were discrepancies between the in vivo RNA sequences and the sequences of virus isolates, indicating that the isolation procedure may select for nonrepresentative virus variants.
authors.affiliation: Department of Virology, National Bacteriological Laboratory, Stockholm, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Albert
authors.forename: J
authors.initials: J
authors.lastname: Wahlberg
authors.forename: J
authors.initials: J
authors.lastname: Lundeberg
authors.forename: S
authors.initials: S
authors.lastname: Cox
authors.forename: E
authors.initials: E
authors.lastname: Sandström
authors.forename: B
authors.initials: B
authors.lastname: Wahren
authors.forename: M
authors.initials: M
authors.lastname: Uhlén
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000188:drug therapy* / Q000382:microbiology; D000595:Amino Acid Sequence; D004352:Drug Resistance, Microbial / Q000235:genetics; D014644:Genetic Variation; D005838:Genotype; D054303:HIV Reverse Transcriptase; D015497:HIV-1 / Q000187:drug effects / Q000201:enzymology / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000382:microbiology; D008297:Male; D008969:Molecular Sequence Data; D012367:RNA, Viral / Q000235:genetics*; D012194:RNA-Directed DNA Polymerase / Q000235:genetics*; D012689:Sequence Homology, Nucleic Acid; D015215:Zidovudine / Q000494:pharmacology* / Q000627:therapeutic use
chemical_list: D012367:RNA, Viral; D015215:Zidovudine; D054303:HIV Reverse Transcriptase; D012194:RNA-Directed DNA Polymerase