Abstract
Abstract Following a mandate from EFSA, the EFSA Panel on Genetically Modified Organisms (GMO Panel) addressed the food and feed risk assessment of genetically modified plants containing stacked transformation events (‘stacks’). The GMO Panel examined the experience gained in the assessment of stacks in the last 20 years. Based on this, the GMO Panel concluded that under specific conditions, field trials for comparative analysis may not always be required for the assessment of stacks and a derogation may be considered. The conditions are: all the events combined in the stack should express traits through newly expressed proteins (NEPs) and these should not be metabolic modifiers. Under the same conditions and in the absence of interactions affecting NEP expression levels, a derogation from current requirements for dietary exposure assessment may also be considered. The GMO Panel also proposes improvements for applicants regarding the presentation of molecular characterisation data for stacks.