Two non-isotopic polymerase chain reaction (PCR) methods were evaluated by testing blood from 41 HIV-1-seropositive and 16 HIV-1-seronegative Ugandan mothers and 56 of their children (aged 0.5-15.0 months). Amplification of HIV-1 sequences was performed in duplicate using a biotinylated primer pair to the gag region (SK 462-431) and nested primer pairs (JA 17-20) to the pol region of HIV-1. gag sequences were hybridized using a microtiter plate coated with the SK 102 probe followed by colorimetric detection using an avidin-horseradish peroxidase conjugate and tetramethylbenzidine/peroxide substrate. pol sequences were detected on agarose gel stained with ethidium bromide. Results of HIV-1 PCR analysis showed that 40 out of 41 (98%) seropositive mothers and 10 out of 29 (34%) seropositive children had detectable HIV-1 gag and pol sequences. None of the 16 seronegative mothers nor 27 seronegative or Western blot-indeterminate children had detectable HIV-1 sequences. Our results suggest that non-isotopic PCR methods are sensitive, specific, and potentially useful in the early diagnosis of HIV-1 infection in developed and developing countries.