Back in 2018, researchers had what seemed like a brilliant plan to decrease the number of disease-carrying mosquitos. Teams genetically modified populations of the blood-sucking pests to make them infertile so that they couldn’t reproduce successfully. In theory, this would drop the mosquito population as a whole. Once the modified insects integrated with the wild ones, their offspring would die.
Now, research shows that the experiment wasn’t a success. In fact, it is completely backfiring. According to an article published by New Atlas, mosquito populations in Brazil are on the rise. As if that wasn’t bad enough, new hybrids are more robust than their ancestors.
Mosquitos are a huge cause for concern. Though their bite and the itchy red bumps left behind are annoying, the insects can actually be deadly in many places around the world. As the number one carrier for diseases like malaria and Zika, mosquitos pose a massive health risk to people living in warm, humid areas.
Thanks to climate change, experts believe that this problem will only continue to grow in the future. As such, it makes sense that scientists are trying to put a dent in their populations. From engineering a fungus that produces spider venom to directly altering the pests’ DNA, many of these efforts use untested methods.
However, this attempt is worse than a failure—it’s a disaster. Although tweaking the reproductive genes of test mosquitos caused populations in Jacobino, Brazil to drop for a few months, this seems to be a temporary result. Unfortunately, just 18 months after the experiment, the number of mosquitos is right back to the original level.
The new bugs appear to be stronger and more resistant to such attempts at genetic alteration than their non-hybrid ancestors.
According to Jeffery Powell, a researcher at Yale, “The claim was that genes from the release strain would not get into the general population because offspring would die. That obviously was not what happened.”
The mosquitos resurfacing in Brazil are something that humanity hasn’t necessarily had to deal with outside of the lab—a genetically modified organism thriving on its own in nature. As a sort of runaway science project, there is no definitive answer of what will happen next.
Though scientists don’t believe that the new hybrid mosquitos are any more dangerous than normal ones, there is no way to be certain. Nor can they predict what other changes will develop in future generations.
Powell commented on this phenomenon saying, “It is the unanticipated outcome that is concerning.”
Of course, it’s possible that nothing bad could come of this. It’s also highly plausible that battling mosquito populations in this area just got a lot harder. Should the hybrids spread from the original location, then the problem could get even broader.
Nonetheless, this backfired experiment goes to show that society isn’t ready for the consequences (identified or not) of genetic engineering. Until our control over genetics and our ability to anticipate all potential outcomes drastically improve, such untested experiments must be considered more carefully or halted altogether.