Practicality of detection of genetically modified organisms (GMOs) in food

The increase in new GMOs (genetically modified organisms) has led to specific legislation world-wide to regulate the presence and/or the amount of GMOs in food, food ingredients, feeds and agriculture commodities. Regulatory demands of labelling and traceability of GMOs in the food chain need suitable sampling protocols and analytical methods. At present, two main techniques, the DNA-based polymerase chain reaction (PCR) and the protein-based enzyme-linked immunosorbent assay (ELISA) are most widely used, although new technologies, such as microarrays, have been also developed. The highly specific and sensitive real-time PCR (RT-PCR) is the method of choice for GMO quantitative estimatation. The potential and the limits of PCR and the practicality of RT-PCR for GMO detection are discussed in the light of actual legislation and of the constraints imposed by the food production chain.