Summary : This project has shown that new methods are available for the detection of so-called unintended effects, which may occur as a result of genetic modification. These methods are based on overall measurements of differences in plant gene expression, or of macro- and micro nutrients and expressed secondary plant metabolites, in contrast to classical methods determining single compounds. The mRNA fingerprinting techniques is useful for the detection of unintended effects at the genome level, in particular applicable during research and development. The chemical fingerprinting technique, using LC-NMR, appears a powerful screening method for the detection of secondary effects which may applied on routine basis. Application fo this method in combination with other measurements of for example agronomical traits, may limit or even replace animal feeding studies aimed at the detection of unintended effects.