Sequence and drug susceptibility of subtype C reverse transcriptase from human immunodeficiency virus type 1 seroconverters in Zimbabwe

Robert W. Shafer, Jonathan A Eisen, Thomas C. Merigan, David A. Katzenstein

Research output: Contribution to journalArticle

60 Scopus citations


Naturally occurring human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) variability has implications for the success of antiretroviral therapy. We determined the sequence of the polymerase-coding region of RT from virus isolates from 12 Zimbabwean individuals recently infected with HIV-1. The 12 RT sequences differed from the consensus B RT sequence at 10.5% of nucleotides and 5.8% of amino acids. Susceptibility testing of five isolates to zidovudine, didanosine, lamivudine, and nevirapine demonstrated susceptibilities similar to those of wild-type subtype B isolates. Phylogenetic analysis of 40 HIV-1 RT sequences, including the 12 Zimbabwean subtype C sequences, 11 subtype B sequences, and the 17 remaining published non-subtype B sequences showed sufficient intrasubtype RT sequence variation to differentiate subtype A, B, C, and D isolates. Five recently reported subtype C RT sequences from India grouped with the Zimbabwean subtype C sequences but had significantly less intraisolate sequence variation. Both intra- and intersubtype RT comparisons were notable fur extraordinarily high ratios of synonymous to nonsynonymous differences. Although substitutions in the HIV-1 RT gene are limited by functional constraints, variation between RT sequences demonstrates phylogenetic relationships that parallel env and gag gene variation.

Original languageEnglish (US)
Pages (from-to)5441-5448
Number of pages8
JournalJournal of Virology
Issue number7
StatePublished - Jul 1997
Externally publishedYes


ASJC Scopus subject areas

  • Immunology

Cite this