The method, protocol describes a technique of how double-stranded DNA probes, labeled in each strand, are produced in conventional PCRs containing equal concentrations of two primers, a double-stranded DNA template, three unlabeled dNTPs at concentrations exceeding the Km, and one [{alpha}-32P]dNTP at a concentration at or slightly above the Km (2-3 µm) for a thermostable DNA polymerase such as Taq.

Protocol: Radiolabeling of DNA Probes by the Polymerase Chain Reaction Protocol