Template usage is responsible for the preferential acquisition of the K65R reverse transcriptase mutation in subtype C variants of human immunodeficiency virus type 1.

McGill University AIDS Center, McGill University, Lady Davis Institute for Medical Research, Sir Mortimer B. Davis Jewish General Hospital, Montréal, Canada.
Journal of Virology (Impact Factor: 4.65). 01/2009; 83(4):2029-33. DOI: 10.1128/JVI.01349-08
Source: PubMed

ABSTRACT We propose that a nucleotide template-based mechanism facilitates the acquisition of the K65R mutation in subtype C human immunodeficiency virus type 1 (HIV-1). Different patterns of DNA synthesis were observed using DNA templates from viruses of subtype B or C origin. When subtype C reverse transcriptase (RT) was employed to synthesize DNA from subtype C DNA templates, preferential pausing was seen at the nucleotide position responsible for the AAG-to-AGG K65R mutation. This did not occur when the subtype B RT and template were used. Template factors can therefore increase the probability of K65R development in subtype C HIV-1.

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