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G. A. Kleter1, H. A. Kuiper1, E. J. Kok1, and R. D. SHILLITO2. (1) State Institute for Quality Control of Agricultural Products (RIKILT), Wagenigen Univ. & Research Centre, PO Box 230, Wageningen, 6700 AE, Netherlands, (2) External Technical Services, Americas, Bayer CropScience LP, 2 T.W. Alexander Dr., PO Box 12014, Research Triangle Park, NC 27709-2014 Modern biotechnology has widened the scope of opportunities for the nutritional improvement of food and feed crops. Some of the crops that have been generated by modern biotechnology for this purpose have undergone complicated modifications, such as the introduction of multiple genes encoding non-intrinsic metabolic pathways. It is anticipated that such complex modification may bear a greater likelihood of unintended effects compared to the comparative simple modifications of the major transgenic crops that are currently marketed. Unintended effects, though, are not unique to crops derived through modern biotechnology and some similarities exist between recombination of DNA in transgenic and conventionally bred crops. Approaches to identify unintended effects currently rely upon the Comparative Safety Assessment of a transgenic crop versus an appropriate conventional counterpart with a history of safe use, including compositional analysis of key parameters, including macro-and micro-nutrients, antinutrients, and toxins. This procedure has been adequate and robust and may in future be complemented by advanced "profiling" methods to obtain indiscriminate, holistic profiles at the gene/RNA (genome)-, protein (proteome)-, and metabolite (metabolome)-levels. Compositional analysis on single compounds is facilitated by knowledge on the key compounds determining the nutritional and toxicological characteristics of crops with a history of substantial and safe consumption. Analytical profiling techniques may provide complementary data for, among others, crops with limited database or that have undergone extensive modifications. Currently, profiling methods are not ready for routine application in safety assessment, while they may be applied in the stage of product development. In case uncertainties in the comparative safety assessment remain, animal tests may be considered to test for unintended effects in the nutritional- and toxicological- characteristics of a transgenic crop.
Session 26, The safety and nutrional assessment of nutrionally improved crops
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