Less Extensive Risk Assessment of GM Stacked Events

GM stacked events are products with more than one transformation event. These have been also referred to as ‘stacked products’, ‘breeding stacks’, ‘stacked genes’ or ‘pyramided traits’. Because they are considered as new GMOs by the European Commission, they need regulatory approval, including an assessment of their safety, similar to single events prior to marketing.

Researchers in Belgium however, assert that the risk assessment of these GM stacked events could be less extensive than the assessment of the parental GM events. The researchers proposed and enumerated several criteria for the risk assessment of stacked events that include molecular and comparative analysis data as minimum requirements. Additional analysis may be conducted in order to extrapolate data from the parental GM lines to the GM stacked event.

 The researchers recommend that the molecular data should include (1) evidence of the presence and the copy number of the parental inserts in the GM stack, and (2) that the levels of expression of the newly expressed proteins in the GM stack is equal to that of the GM parental lines. In addition, the combined effects of the transgenes and the effects of the potential interactions between the newly expressed proteins should also be assessed.

The opinion paper published by the journal Trends in Food Science and Technology can be accessed by subscribers at http://dx.doi.org/10.1016/j.tifs.2006.09.002.