Incorporation of 2-OH-dATP by DNA polymerases. The incorporation of 2-OH-dATP into DNA by the following enzymes was assayed: P1 DNA polymerase Y1 (A), P2 DNA polymerase Y1 (B), hDNA polymerase η (C), KF exo− (D) and DNA polymerase B1 (E). Cy3-labelled-primer 2/template 2 (0.1 μM) was incubated with P1 DNA polymerase Y1 (200 nM), P2 DNA polymerase Y1 (25 nM), hDNA polymerase η (1 nM), DNA polymerase B1 (25 nM) or KF exo− (0.02 units) in the presence of 50 μM 2-OH-dATP.