PCR detection of genetically modified soybean and maize in food/feed stuffs

Abstract

Public concern about possible negative health effects due to consumption of GM plants, together with concerns about possible environmental dangers, have led the European Commission to limit strictly the distribution of GM plants in the EU. The EU regulations No 49 and 50/2000 require the food industry to label, as GMO containing, those food products not certified free of transgenic plant material Foods are considered "clean" and may be left unlabeled, if the GM content does not exceed 1%. The presence of GM in food and feed products can be evaluated by detecting the transgenic DNA (PCR technique), or by detecting proteins derived from this DNA (immunological methods). At the Institute of Molecular Genetics and Genetic Engineering, both qualitative and quantitative PCR-based tests are standardized. Commonly used primers are designed from the CaMV35S promoter for the answer yes/no in general GMO screening procedure. Specific modifications, as in herbicide tolerant RoundUp Ready Soybean or insect resistant maize (Bt176 corn), are identified by primers designed from specific genes e.g. the EPSPS - gene from A.tumefaciens (for soybean) and the Cry1A gene from B.thuringiensis (for maize). The experimentally determined detection limit is 1pg, which allows detection of 0,01% GM DNA in test-samples and meets criteria prescribed for the EU laboratories accredited to issue a certificate.