The VisionArray Uracil-DNA (UDG) Glycosylase is an E. coli derived enzyme intended to be used to prevent carry-over contaminations from previous reactions. This is based on the principle of substituting dUTPs for dTTPs during PCR. Therefore the PCR amplificate can be “discriminated” from the initital DNA strand. Incubating the PCR mixture with the UDG enzyme at elevated temperatures under alkaline conditions (during the initial denaturation step) will remove contaminating U-DNA from the sample thereby avoiding false positive results.