Scientists have engineered a male fruit fly that when introduced into a fly population eventually brings about the population’s “collapse”—because it can only successfully father sons. The discovery that could potentially be used to save crops in an environmentally friendly and cost effective manner, the BBC reports:
The Mediterranean fruit fly is a global agricultural pest which infests over 300 crops, including wild fruit, vegetables and nuts, causing extensive damage. […] Currently, techniques for pest control include sterilisation and insecticides. However, sterile flies do not mate as well in the wild as the process to make them sterile weakens them. Insecticide also poses problems as flies can quickly develop immunity.The male GM flies produced by Oxfordshire-based biotechnology company Oxitec are only capable of producing male offspring. They have what Oxitec calls “pre-pupal female lethality”. In other words, a female specific gene kills the females before they become adults.This means that after several generations, the flies die off as the males can no longer find mates.
This ability to introduce “sex bias” into insect populations could change the way we go about protecting crops from insects. Currently, farmers pair insecticides with crops that have been genetically modified to resist the toxin, but the introduction of this genetic variant into pest populations could preempt that.And this isn’t just a solution for crops—the company developing this technology has conducted “extensive field trials with GM mosquitoes in Brazil in order to prevent the spread of dengue fever, killing 96% of the dengue-spreading mosquitoes.” Mosquitoes pose an enormous global health threat; killing them could save millions of lives.Genetic modifications have enormous potential to change the world for the better. These technologies are off-putting for some who see them as “unnatural,” and in some cases pose difficult ethical questions. But the green revulsion for “frankenfoods” or a general squeamishness about the concept of mutant flies shouldn’t get in the way of solutions that can help feed our planet’s growing population and help eradicate dangerous disease vectors.