The Direct Blood PCR Kit allows to use whole blood stored at +4°C or -20°C as well as dried blood spots on cards such as commercially available Whatman FTA^® cards. Blood can be preserved with all most often used anticoagulants: EDTA, citrate or heparin. It is possible to use whole blood in a wide range of concentrations: from 1 % to 20 %. The recommended starting point is 5 % (MgCl₂ concentration contained in the Blood PCR buffer is optimized for 5 % blood). The Direct Blood PCR Kit employs a genetically engineered thermophilic DNA polymerase with high tolerance to blood inhibitors. Enhanced polymerase processivity allows to use shorter extension times. Due to the genetic modification of the polymerase, the optimal reaction conditions (especially annealing temperatures) differ from standard PCR protocols. The Direct Blood PCR Kit allows to obtain a wide range of product size (over 4 kb).