New England Biolabs’ recently developed a novel high-fidelity DNA polymerase, the Q5 High-Fidelity DNA Polymerase, that is a fusion with the Sso7d DNA-binding domain. It enables reduced extension times of about 10 seconds per kilobase and fidelity 100-fold higher than Taq. Bio-Rad's high-fidelity, high-processivity PCR reagents also contain the double-stranded DNA-binding protein Sso7d, and are fused to a proofreading polymerase. Their iProof DNA polymerase can amplify long and difficult targets quickly, and is tolerant to PCR inhibitors present in some samples.