Release of genetically engineered insects: a framework to identify potential ecological effects

Abstract

Genetically engineered (GE) insects have the potential to radically change pest management worldwide. With recent approvals of GE insect releases, there is a need for a synthesized framework to evaluate their potential ecological and evolutionary effects. The effects may occur in two phases: a transitory phase when the focal population changes in density, and a steady state phase when it reaches a new, constant density. We review potential effects of a rapid change in insect density related to population outbreaks, biological control, invasive species, and other GE organisms to identify a comprehensive list of potential ecological and evolutionary effects of GE insect releases. We apply this framework to the Anopheles gambiae mosquito – a malaria vector being engineered to suppress the wild mosquito population – to identify effects that may occur during the transitory and steady state phases after release. Our methodology reveals many potential effects in each phase, perhaps most notably those dealing with immunity in the transitory phase, and with pathogen and vector evolution in the steady state phase. Importantly, this framework identifies knowledge gaps in mosquito ecology. Identifying effects in the transitory and steady state phases allows more rigorous identification of the potential ecological effects of GE insect release.

Concerning RNA-guided gene drives for the alteration of wild populations

“…Frameworks for evaluating ecological consequences are similarly focused on mosquitoes (David et al, 2013) and the few other organisms for which alternative genetic biocontrol methods have been considered (Dana et al, 2014). While these examples provide an invaluable starting point for investigations of RNA-guided gene drives targeting other organisms, studies examining the particular drive, population, and associated ecosystem in question will be needed.…”

“…While considerable scholarship has been devoted to the question of how gene drives might be safely utilized in mosquitoes (Scott et al, 2002; Touré et al, 2004; Benedict et al, 2008; Marshall, 2009; UNEP, 2010; Reeves et al, 2012; David et al, 2013; Alphey, 2014), few if any studies have examined the potential ecological effects of gene drives in other species. After all, constructing a drive to spread a particular genomic alteration in a given species was simply not feasible with earlier genome editing methods.…”

Genetic engineering to eradicate invasive mice on islands: modeling the efficiency and ecological impacts

“…Even though the increase in mouse population density would only be temporary during the beginning of the eradication process, its resulting effects on the ecosystem could be permanent (David et al 2013, Esvelt et al 2014, especially if the temporary increase in mouse density results in the extinction of a rare species. Namely, shortterm impacts can have long-term ramifications.…”

Concerning RNA-Guided Gene Drives for the Alteration of Wild Populations

“…Fourth, our current knowledge of the risk management 5,11,36,37,95 and containment 35,38 issues associated with gene drives is largely due to the efforts of researchers focused on mosquito-borne illnesses. Frameworks for evaluating ecological consequences are similarly focused on mosquitoes 39 and the few other organisms for which alternative genetic biocontrol methods have been considered 96 . While these examples provide an invaluable starting point for investigations of RNA-guided gene drives targeting other organisms, studies examining the particular drive, population, and associated ecosystem in question will be needed.…”

“…While considerable scholarship has been devoted to the question of how gene drives might be safely utilized in mosquitoes 5,11,[35][36][37][38][39][40] , few if any studies have examined the potential ecological effects of gene drives in other species. After all, constructing a drive to spread a particular genomic alteration in a given species was simply not feasible with earlier genome editing methods.…”