Genetically modified organisms GMO

Within the framework of safety assessment of food produced by means of modern genetic engineering the comparative analysis of the genetic modified (GM) crop with its unmodified genetic counterpart is an important part [36]. Two approaches are followed to detect intentional or unintentional alteration of the chemical composition of the GMO, i.e., a targeted approach (i.e., investigating defined constituents) and an untargeted approach using profiling technologies to analyse differences in RNA, proteins and metabolites [37]. Targeted analysis of single compounds with focus on important nutrients and critical toxicants has been successfully applied to demonstrate the safety of GM foods. Some criticisms have been expressed on the targeted approach as being biased and focused on known compounds and expected results [38]. This may become increasingly a problem in the second generation of GM crops where the introduction of completely new biosynthetic pathways or modifications in key enzymes in the primary or secondary structure may result in unexpected changes. Non-targeted approaches using profiling technologies based on DNA (e.g., microarray methods), proteins (two-dimensional gel electrophoresis followed by MSand/ or metabolites (using e.g., nuclear magnetic resonance (NMR), GC/MS and LC/ MS) are nowadays explored for their potential within the food safety assessment of GM food crops.

In the EU the release of GMO and GMO-derived ingredients into the environment, and the marketing of GMO-derived food and animal feed is regulated within various specific directives and regulations. The EU regulations 1829/2003 and 1830/2003 concern the premarket safety assessment and the traceability and labeling of food and feed products derived from authorized GMOs establish that food or feed materials containing GMO-derived ingredients above the set threshold of 0.9% must be labeled as such. Implementation and enforcement of this regulation is generally performed by PCR-based methods using GMO-specific DNA probes. These methods must meet a number of agreed quality requirements. On the other hand, the presence of unauthorized GMO is not allowed at all in food and feed. In these cases, qualitative methods, such as DNA microarray methods may in the near future become very useful since these methods allow the detection of many different GMOs and GMO elements in one analysis, albeit their quantitative performance is limited [39]. Major challenges in GMO detection are quantitative aspects, validation and harmonization. Knowledge about the measurement uncertainty at the level of 0.9% is crucial already, and once a minimum required performance level (MRPL) has been assigned to the ban on unauthorized GMO that challenge will become immense.

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