title: Naturally occurring sequence polymorphisms within HIV type 1 group O protease.
abstract: Mutations within the protease gene associated with reduced susceptibility to protease inhibitors have been well documented for HIV-1 group M subtype B strains. In contrast, limited genotypic and phenotypic information is available for the genetically diverse HIV-1 group O strains. Preexisting resistance-associated polymorphisms have the potential to contribute to a poor virological response to antiviral drug treatment in group O-infected patients. In the present study, the protease genes of 28 protease inhibitor-naive HIV-1 group O-infected patients were analyzed to identify any naturally occurring amino acid polymorphisms associated with drug resistance. Comparison of the consensus group O protease sequence with subtype B of group M indicated that both groups have almost identical sequences in the protease active site, the flap and the substrate-binding site. Analysis of the 28 individual protease sequences revealed polymorphisms at 34% of the positions within the protease gene, but no primary mutations associated with protease inhibitor resistance. In contrast, each of the strains harbored multiple secondary or accessory mutations associated with resistance to protease inhibitors in group M viruses. Residues 10I, 15V, 36I, 41K, 62V, 63T/A/K/I, 64V, 71V, and 93L were identified in most strains. The presence of multiple natural sequence polymorphisms associated with drug resistance in the protease gene of group O viruses may contribute to a more rapid emergence of drug resistance phenotype and treatment failure in group O-infected patients.
authors.affiliation: AIDS Research and Retrovirus Discovery, Abbott Laboratories, Abbott Park, Illinois 60064, USA.
authors.forename: K C
authors.initials: KC
authors.lastname: Luk
authors.forename: L
authors.initials: L
authors.lastname: Kaptué
authors.forename: L
authors.initials: L
authors.lastname: Zekeng
authors.forename: V
authors.initials: V
authors.lastname: Soriano
authors.forename: L
authors.initials: L
authors.lastname: Gürtler
authors.forename: S G
authors.initials: SG
authors.lastname: Devare
authors.forename: G
authors.initials: G
authors.lastname: Schochetman
authors.forename: J
authors.initials: J
authors.lastname: Hackett
mesh_terms: D000595:Amino Acid Sequence; D015658:HIV Infections / Q000188:drug therapy* / Q000821:virology; D016333:HIV Protease / Q000235:genetics*; D015497:HIV-1 / Q000145:classification* / Q000201:enzymology* / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D010802:Phylogeny; D011110:Polymorphism, Genetic / Q000235:genetics*; D011480:Protease Inhibitors / Q000627:therapeutic use*; D017422:Sequence Analysis, DNA
chemical_list: D011480:Protease Inhibitors; D016333:HIV Protease