Hot Start Taq DNA Polymerase is a mixture of Taq DNA Polymerase and an aptamer-based inhibitor. The inhibitor binds reversibly to the enzyme, inhibiting polymerase activity at temperatures below 45°C, but releases the enzyme during normal cycling conditions, allowing reactions to be set up at room temperature. This aptamer-based hot start does not require a separate high temperature incubation step to activate the enzyme. Taq DNA polymerase possesses a 5´→3´ polymerase activity (1)(2)(3)and a 5´ flap endonuclease activity(4)(5).