People in the Florida keys distrust and oppose the plan to wipe out Aedes aegypti mosquitoes locally with an experimental gene drive.

Using gene drive to wipe out a noxious species is potentially very useful. It also carries imponderable risks, which might be small, but it is not clear that we have done enough to be sure that is true. I don't know whether we are ready to try the technique in the wild.

We could reduce these risks by including a way to deactivate the gene drive. Here's one idea: make it depend on a promoter that detects the presence of some harmless but unusual chemical which will disappear from the the environment in a few weeks or months. We could strew that around the experimental area, and continue providing it for as long as needed, but stop if anything goes wrong.