Workshop on the problem formulation for the environmental risk assessment of gene drive modified insects

On 15 May, EFSA met stakeholders and EU Member States to discuss plausible environmental risks associated with the release of gene drive modified insects into the environment. Gene drives consist of genetic elements that can pass traits among sexually reproducing individuals with higher efficiency than expected under Mendelian inheritance.

This emerging technology has sparked both enthusiasm and concerns. While gene drives could be used to control agricultural pests and invasive species, rescue endangered species or supress disease vectors, there is concern that they may lead to undesired side effects and alter ecosystems in irreversible ways.

During the workshop participants used problem formulation to:

1. Formally devise plausible pathways to harm that describe how the deployment of gene drive modified insects could be harmful;
2. Formulate risk hypotheses about the likelihood and severity of such events;
3. Identify the information that will be useful to test these risk hypotheses;
4. Identify how to acquire new data for hypothesis testing should tests with existing information be insufficient for decision-making.

The problem formulation exercise was run for two case studies in two separate discussion groups: (1) self-sustaining gene drives to control disease-spreading mosquitoes (e.g. Aedes albopictus), and (2) self-sustaining gene drives to control agricultural pests (e.g. Drosophila suzukii).

The input collected from participants will support EFSA’s expert working group on the environmental risk assessment of gene drive modified organisms to frame its work in the broader societal context. This working group has been mandated by the European Commission to assess the adequacy of existing risk assessment guidelines for gene drive modified insects. Potential risks that such organisms could pose in terms of impact on human and animal health and the environment will also be taken into consideration while maintaining a distinction between risk assessment and risk management aspects.

The programme included presentations from experts in the field and group discussions. The outcome of the debates was presented and discussed in a final plenary session to draw the conclusions of the workshop.