A DNA polymerase mutant comprising a Taq DNA polymerase amino acid sequence with a mutation at one or more of the following selected amino acid positions: E189K, E230K, E507K, H28R, L30R, G38R, F73V, H75R, E76A, E76G, E76K, E90K, K206R, E315K, A348V, L351F, A439T, D452N, G504S, E507A, D551N, L552R, I553V, D578N, H676R, Q680R, D732G, E734G, E734K, F749V; wherein the polymerase mutant exhibits relative to wild-type DNA polymerase increased polymerase speed, increased affinity to DNA substrate and/or increased resistance to a DNA polymerase inhibitor; and wherein, when the mutation is E507K in combination with two or more further mutations or the mutation is Q680R in combination with four or more further mutations, at least one of the further mutations is at one of the selected amino acid positions; and when the mutation is I553V, this is not in combination with D551S.