Hot start DNA polymerase is a modified form of DNA polymerase which avoids a non-specific amplification of DNA by inactivation of the taq polymerase at low temperatures. The polymerase chain reaction (PCR) is a technology in molecular biology used to amplify a single copy or a few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence. In Hot start PCR, specific antibodies are used to block the Taq-polymerase at lower temperature. An initial step at 95℃ is required for denaturing the antibodies linked to the active center of the enzyme. The anti-Taq antibodies reduce the Taq polymerase activity below 72℃, the optimal temperature at which the enzyme extends the primers. When the specific antibodies detach from Taq-polymerase, the amplification proceeds with greater specificity.Reduction of the PCR reaction time allows both time saving and the possibility of processing more samples. When using conventional DNA polymerase for fast PCR, this often results in a reduction of sensitivity and an increase in errors in sequence amplification. This is why it is important to use a DNA polymerase optimized for fast PCR in order to maintain the quality of the sequence while reducing the time necessary for its amplification.