Stakeholder workshop “Problem formulation for the environmental risk assessment of gene drive modified insects” (15 May 2019, Brussels)

Abstract

Recent advances in molecular and synthetic biology are enabling the engineering of gene drives that spread genes of interest through interbreeding populations at a frequency greater than the rate expected by simple Mendelian inheritance. At present, insects represent the most likely cases of gene drive modified organisms for deliberate release into the environment. Through an open workshop, the European Food Safety Authority (EFSA) aimed to engage with stakeholders to discuss potential environmental risks associated with the deliberate release into the environment of gene drive modified insects. Workshop participants were invited to contribute to an example problem formulation to: (1) identify relevant broad protection goals and make them operational for use in environmental risk assessment; (2) formally devise examples of plausible pathways to harm that describe how the deployment of gene drive modified insects could be harmful; (3) formulate example risk hypotheses about the likelihood and severity of such events; (4) identify possible information that would be useful to test these risk hypotheses; and (5) identify how to acquire new data for hypothesis testing when existing information is deemed insufficient for regulatory decision-making. The problem formulation exercise was run for two hypothetical case studies (i.e. self-sustaining low threshold gene drives to control disease-spreading mosquitoes (Aedes albopictus, the Asian tiger mosquito) and agricultural pests (Drosophila suzukii, the spotted-wing Drosophila)). Points raised by the workshop participants reveal different often contrasting opinions/perspectives toward gene drive and their risk assessment. Overall, there was agreement that the problem formulation process is fit-for-purpose for the environmental risk assessment of gene drive modified insects, but it was acknowledged that practical challenges may be encountered. Points raised by the workshop participants, on defining protection goals, formulating specific pathways to harm and on structuring risks, have been considered by EFSA's Panel on genetically modified organisms during its deliberations.