Résumé
The outcrossing of genetically modified (GM) plants to wild relatives, and the subsequent spread of transgenes in nature are key elements in the environmental risk assessment of experiments involving GM plants and crops. Given the possible introduction of crops developed using new genomic techniques (NGTs) into the environment, it is important to determine whether introgression from cultivated plants to their wild relatives occurs, how it can be detected, the factors that contribute to it, the scale of its occurrence and its potential impact on wild populations. To gain more insight into this issue, Margret Veltman of the French National Institute for Sustainable Development (IRD) in Montpellier conducted a literature review on behalf of COGEM. The research presented focuses on all genera and species in which research into introgression from cultivated plants to wild relatives has been conducted. The report provides a comprehensive overview of the technical possibilities for detecting introgression and the parameters that influence it, as well as studies describing introgression based on frequency in populations or size in genomes.It concludes that introgression into wild relatives is widespread, regardless of reproductive biology or ploidy level, and that it is virtually impossible to prevent introgression from crops into wild relatives, with unpredictable consequences.