FIG. 1.

The sensitivity of the OLA was evaluated for the detection of HIV-1 genotypes of low prevalence. Mixtures of wild-type and drug-resistant genomes derived from plasmid DNA were prepared. One nanogram of DNA from each mixture was PCR amplified and evaluated by the OLA. The mean absorbance readings (± SD) for four or six reactions are shown for mutant genome (shaded bars, OD₄₉₀) and wild-type genome (white bars, OD₄₅₀). Low concentrations (5%) of mutant and wild-type genomes were detected both by OD readings and direct observation of color in the microtiter plate wells.