title: Prevalence of the K65R resistance reverse transcriptase mutation in different HIV-1 subtypes in Israel.
abstract: The K65R mutation in HIV-1 reverse transcriptase (RT) can be selected by the RT inhibitors tenofovir (TDF), abacavir (ABC), and didanosine (DDI). Recently, in vitro studies have shown that K65R is selected in tissue culture more rapidly with subtype C than subtype B viruses. The prevalence of K65R in viruses sequenced at the Tel-Aviv AIDS Center was evaluated. This study analyzed retrospectively sequences from 1999 to 2007 in patients treated with TDF, ABC, and/or DDI and compared rates of mutational prevalence between subtypes. Fisher's exact test was used to determine statistical significance. Forty-four sequences from patients treated with the three above-cited drugs were analyzed. Subtypes A (n = 1), CRF01_AE (n = 4), CRF02_AG (n = 2), B (n = 21), C (n = 11), D (n = 1), F (n = 3), and G (n = 1) were represented. Seven non-B viruses had the K65R mutation, which was only found in one subtype B virus. Of these seven samples four were subtype C, one was subtype CRF01_AE, and two were subtype CRF02_AG. None of the eight viruses with K65R harbored thymidine analogue mutations. In this study, non-subtype B viruses possessed the K65R mutation at higher incidence than subtype B viruses. Subtype C viruses may be especially prone to develop this mutation. Larger studies are needed to confirm these data. Efforts should be intensified to understand better differences in drug resistance between various HIV subtypes.
authors.affiliation: Kobler AIDS Center, Infectious Diseases Unit, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel. dan.turner@tasmc.health.gov.il
authors.forename: Dan
authors.initials: D
authors.lastname: Turner
authors.forename: Eduardo
authors.initials: E
authors.lastname: Shahar
authors.forename: Eugene
authors.initials: E
authors.lastname: Katchman
authors.forename: Eynat
authors.initials: E
authors.lastname: Kedem
authors.forename: Natasha
authors.initials: N
authors.lastname: Matus
authors.forename: Michal
authors.initials: M
authors.lastname: Katzir
authors.forename: Gamal
authors.initials: G
authors.lastname: Hassoun
authors.forename: Shimon
authors.initials: S
authors.lastname: Pollack
authors.forename: Rivka
authors.initials: R
authors.lastname: Kessner
authors.forename: Mark A
authors.initials: MA
authors.lastname: Wainberg
authors.forename: Boaz
authors.initials: B
authors.lastname: Avidor
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D019380:Anti-HIV Agents / Q000494:pharmacology*; D024882:Drug Resistance, Viral; D005260:Female; D005838:Genotype; D015658:HIV Infections / Q000821:virology*; D054303:HIV Reverse Transcriptase / Q000235:genetics*; D015497:HIV-1 / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D006801:Humans; D007557:Israel; D008297:Male; D008875:Middle Aged; D020125:Mutation, Missense; D015995:Prevalence; D012189:Retrospective Studies; D018894:Reverse Transcriptase Inhibitors / Q000494:pharmacology*; D017422:Sequence Analysis, DNA; D055815:Young Adult
chemical_list: D019380:Anti-HIV Agents; D018894:Reverse Transcriptase Inhibitors; C514824:reverse transcriptase, Human immunodeficiency virus 1; D054303:HIV Reverse Transcriptase