Screwworm could be the first species targeted by an ‘extinction drive’
In a few cases, the extinction of a species would be a good thing. That’s a controversial opinion, but I do think the world would be better off, for instance, without malaria-spreading mosquitoes. We now have the genetic technology to achieve this, in the form of extinction drives – more accurately called gene drives – that can defy evolution and spread harmful traits throughout a population. Unfortunately, it doesn’t look like this technology will be deployed against malaria-carrying mosquitoes any time soon. Instead, Kevin Esvelt at the Massachusetts Institute of Technology, the biologist who created the first CRISPR-based gene drive, thinks the screwworm (Cochliomyia hominivorax) will be the first in line. “The one that I would bet on is the New World screwworm, that nasty bot fly that’s now been found a couple times in Texas,” says Esvelt. “It’s even more hated than malaria mosquitoes, if you can believe that.” Screwworm flies lay their eggs in wounds on mammals and sometimes birds. When the larvae hatch, they burrow into the flesh of their host and …



