NRTI resistance of HIVs with mutations at RT residue 70 in the background of WT or Q151Mc.

Antiviral activities of HIV-1s carrying mutations at residue 70 (K70R, K70G, K70E, K70T, K70N, or K70Q) in the WT (A) or Q151Mc (B) background were determined by the MAGIC5 assay. The data for each clone were compared to WT (A) and Q151Mc (B) HIV-1 and are shown as fold increase; AZT (red), ddI (green), d4T (cyan), 3TC (orange), ABC (blue), and TFV-DF (purple). Error bars represent standard deviations from at least three independent experiments (see also Table S2 and Table S3). The asterisk indicates statistically significant in EC₅₀ values (P<0.0001 by t-test).