Table 5.

Previously proposed risks to human and animal health and the environment associated with the deliberate release of gene drive modified insects considered in this GMO Panel Scientific Opinion

Potential to cause harm to:	Previously proposed risksa
Human health and animal health	Increased disease transmission – Increased abundance of disease‐transmitting insects – Increased competence for transmission of the pathogen or other insect‐borne pathogens and thus the prevalence of other insect‐transmitted diseases – Altered mating, host seeking, or feeding behaviours, or geographic range (broader temperature tolerance) of disease‐transmitting insects – Reduced control capability due insecticide resistance Increased potential for resistance to evolve in the target organism – Reduced efficacy of the gene drive modified insect (GDMI) in the target population(s) Increased toxicity and/or allergenicity – Transmission of toxic or allergenic substances (related to the components of an engineered gene drive) either directly by biting or indirectly by exposure from such substances released into the environment (e.g. incidental exposure through inhalation or ingestion) – Increased pathogen virulence in case of population modification
The environment (biodiversity, food webs, ecosystems and ecosystem services)	Increased persistence and invasiveness potential – A competitive advantage of GDMIs as compared to the wild type, causing increased persistence and invasiveness and leading to the displacement of other insect pest species Increased potential for resistance to evolve in the target organism – Management responses to reduced efficacy of the GDMI Increased potential for vertical and horizontal gene transfer – Spread of the genetic modification of interest to non‐target organisms through vertical and horizontal gene transfer Increased toxicity – Transmission of substances (related to the components of an engineered gene drive) that are toxic to non‐target organisms that consume the GDMI Adverse effects associated with the suppression of the target organism – Suppression of the target organism that serves as food source (e.g. prey) for non‐target organisms (e.g. predator) – Suppression of the target organism may harm non‐target organisms that rely on the species for the delivery of ecosystem services (such as pollination, biological control, decomposition) – Invasion of the ecological niche vacated by suppression of the target organism of another insect pest (e.g. other mosquito species in aquatic habitats during larval stages) (niche replacement) Decreased water quality – Suppression of the target organism (e.g. mosquito larvae in aquatic habitats) which results in reduced larval consumption of algae causing levels of algae to increase and their associated toxins produced from algal bloom. This is in turn could lead to adverse effects on non‐target organisms in the aquatic habitat, and negative effects on water quality

GDMI: gene drive modified insect.

^aBased on NASEM (2016), Roberts et al. (2017), James et al. (2018, 2020), Collins et al. (2019), CSS–ENSSER–VDW (2019), Rode et al. (2019), Teem et al. (2019), Dolezel et al. (2020a,b), Romeis et al. (2020), Smets and Rüdelsheim (2020) and Then et al. (2020).