TIARIS™ High-Fidelity DNA polymerase is a robust enzyme with 3´→ 5´ exonuclease (proofreading) activity and enhanced DNA binding, resulting in improved processivity, yield, and extremely low error-rate. TIARIS™ High-Fidelity DNA polymerase has an error-rate of approximately 1 error per 4.4×107 nucleotides incorporated, which is 50x lower than Taq DNA polymerase. The enzyme is ideal for applications such as high-fidelity PCR, site-directed mutagenesis, crude sample PCR, blunt-end cloning, among others, where robustness and proofreading are important. The supplied reaction buffer (5x) includes not only 15 mM MgCl2, but also 5mM dNTPs, enhancers, and stabilizers, optimized to increased PCR success rates.