Development and validation of a multiplex real-time PCR method for screening genetically modified plants

The diversity of genetically modified plants used for food and feed is increasing worldwide. For the detection and control of these products, efficient and reliable analytical tools are a prerequisite. This can be done by screening for specific DNA-elements and constructs characteristic of transgenic plants. In the past, numerous methods have already been published. However, several genetically modified plants are not covered by common screening methods. Here, a new qualitative triplex real-time polymerase chain reaction (PCR) method is presented, detecting two transgene flanking sequences and the transition between the Cassava Vein Mosaic Virus Promotor (P-CsVMV) and the phosphinothricin-N-acetyltransferase (pat) gene. These sequences are present in several transgenic plants and therefore, the described triplex method can be used as a screening tool to guide further analysis and increase the efficiency of the analysis strategy for GMO detection. The method is characterized by high specificity, sensitivity and robustness and is provided as a ring-trial validated method in the Official Collection of Methods according to the German Food and Feed Act.