A PCR-microarray method for the screening of genetically modified organisms

A new method to screen and to identify genetically modified organisms (GMO) is presented in this paper. It is based on the detection of multiple genetic elements common to GMO by their amplification via PCR followed by direct hybridisation of the amplicons on microarray. The pattern of the elements is then compared to a database of the composition of EU-approved GMO and an identification of the GMO is then proposed. The limit of detection of the method was B0.1% GMO content (w/w) expressed as the amount of target DNA present in the template for single unprocessed material. The DNA targets were detected both in reference materials and in mixtures with the same detection limit. The specificity for the detection of the different elements was found to be very good with no crossreaction even in samples with two GMO present at different concentrations. The paper presents examples of GMO identification and discusses the potential and limitation of such approaches and how they can facilitate the work of private and enforcement detection laboratories.JRC.DDG.I.4-Molecular biology and genomic

GMO sampling strategies in food and feed chains

The sampling step is relevant whenever it is necessary to evaluate an analyte in a lot. However, sampling is by far the most crucial step when the analyte is heterogeneously distributed in the lot, especially at low concentration, because high sampling uncertainty could invalidate the overall analytical testing. The economic and legal implications of such failure could greatly exceed the very high cost of accurate sampling. When there is a legal requirement that the analyte be analytically traced, low sampling reliability at any step of the production and distribution chains could cause the entire traceability system to fail. These considerations also apply to the legally - imposed GMO requirements, particularly those for labelling and traceability. Improper sampling can mislead both food producers and consumers about the GM content in products. In addition, if GMO tests fail to detect an unauthorised GM crop, those unauthorised crops could pose potential risks to human and animal health. Failure of traceability could result in collapse of transgenic and conventional/organic co - existence in the fi eld, with subsequent environmental and economic consequences. A sampling plan should be reliable, cost - effective and feasible in the real life. ‘ Fit - for - purpose ’ sampling plans should be studied and applied, given the wide variety of field situations and ultimate goals. In addition, the uncertainty level of the ‘ overall analytical chain ’ is relevant in many respects, such as making decisions about the best procedures to put in place. Uncertainty in GMO sampling is high, therefore statistical studies should be performed to evaluate sampling uncertainty or at least generate insight into how to make responsible decisions on the most appropriate sampling plan to adopt at each step of the food and feed chain. Prior to the European research project Co - Extra, valuable and indispensible research had been conducted on topics such as the distribution of GMOs in a lot and the implementation of reliable software tools to reveal the most suitable sample size for GMO detection. Research conducted within the Co - Extra project fi lled in relevant theoretical gaps related to the assessment of control plans. All of this research represents a basis for selecting appropriate sampling plans that are best adapted to the operational conditions.JRC.I.3-Molecular Biology and Genomic