title: Lack of detectable human immunodeficiency virus type 1 superinfection during 1072 person-years of observation.
abstract: We examined consecutive protease (PR) and reverse transcriptase (RT) sequences from human immunodeficiency virus (HIV) type 1-infected individuals, to distinguish changes resulting from sequence evolution due to possible superinfection. Between July 1997 and December 2001, >/=2 PR and RT samples from 718 persons were sequenced at Stanford University Hospital. Thirty-seven persons had highly divergent sequence pairs characterized by a nucleotide distance of >4.5% in PR or >3.0% in RT. In 16 of 37 sequence pairs, divergence resulted from the loss of mutations during a treatment interruption or from the gain of mutations with reinstitution of treatment. tat and/or gag sequencing of HIV-1 from cryopreserved plasma samples could be performed on 15 of the 21 divergent isolate pairs from persons without a treatment interruption. The sequences of these genes, unaffected by selective drug pressure, were monophyletic. Although HIV-1 PR and RT genes from treated persons may become highly divergent, these changes usually are the result of sequence evolution, rather than superinfection.
authors.affiliation: Department of Medicine/Division of Infectious Diseases, Stanford University, Stanford, USA.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Gonzales
authors.forename: Eric
authors.initials: E
authors.lastname: Delwart
authors.forename: Soo-Yon
authors.initials: SY
authors.lastname: Rhee
authors.forename: Rose
authors.initials: R
authors.lastname: Tsui
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Zolopa
authors.forename: Jonathan
authors.initials: J
authors.lastname: Taylor
authors.forename: Robert W
authors.initials: RW
authors.lastname: Shafer
mesh_terms: D002140:California; D019143:Evolution, Molecular; D015750:Genes, gag; D015756:Genes, tat; D015658:HIV Infections / Q000821:virology*; D016333:HIV Protease / Q000235:genetics; D054303:HIV Reverse Transcriptase / Q000235:genetics; D015497:HIV-1 / Q000235:genetics* / Q000302:isolation & purification; D006785:Hospitals, University; D009154:Mutation; D010802:Phylogeny; D011159:Population Surveillance; D017423:Sequence Analysis, RNA; D015163:Superinfection / Q000821:virology*
chemical_list: D054303:HIV Reverse Transcriptase; D016333:HIV Protease