Of all the potentially apocalyptic technologies scientists have come up with in recent years, the gene drive is easily one of the most terrifying. A gene drive is a tool that allows scientists to use genetic engineering to override natural selection during reproduction. In theory, scientists could use it to alter the genetic makeup of an entire species — or even wipe that species out. It's not hard to imagine how a slip-up in the lab could lead to things going very, very wrong.
One day scientists could use technology like gene drive to engineer away pests like mosquitoes. IMAGE: Getty Images
But like most great risks, the gene drive also offers incredible reward. Scientists are, for example, exploring how gene drive might be used to wipe out malaria and kill off Hawaii's invasive species to save endangered native birds. Its perils may be horrifying, but its promise is limitless. And environmental groups have been campaigning hard to prevent that promise from ever being realised.
This week at the United Nations Convention on Biodiversity in Mexico, world governments rejected calls for a global moratorium on gene drives. Groups such Friends of the Earth and the Council for Responsible Genetics have called gene drive "gene extinction technology," arguing that scientists "propose to use extinction as a deliberate tool, in direct contradiction to the moral purpose of conservation organisations, which is to protect life on earth."
At the UN meeting, some countries supported the moratorium, which asked for a halt on all research proposals using gene drive technology. The UN's final agreement instead called for caution in field-testing the products of synthetic biology and better efforts to assess potential risk.
Some scientists, though, have already begun urging their colleagues to recognise the potential disasters that gene drive technology could precipitate. MIT synthetic biologist Kevin Esvelt, for example, is working to convince both fellow scientists and research journals to publish research plans before studies are begun, allowing a broad community of scientists to pitch in and assess the potential risk. Esvelt and his colleagues were the first to suggest that the gene-editing technology Crispr could be used to turn the theory of a gene drive into reality. But Esvelt and his colleagues were horrified when other scientists put that suggestion to the test by using gene drive to create a yellow fruit fly, and sought to publish the results in a paper that barely discussed the precautions necessary when working with gene drives. (It didn't help that the researchers chose an apocalyptic title for their fruit fly paper, "The mutagenic chain reaction.")
A growing cadre of scientists has called for caution and openness when it comes to synthetic biology experiments that might impact the public. Researchers have also undertaken efforts to design new gene drive techniques that can help mitigate concerns by limiting any potential long-term effects. Their fear is not just the remote possibility of a lab-created global disaster, but that some highly-publicized accident might cause public outrage that forces research and progress to stop.
Part of the reason people are freaking out is how fast all of this science has progressed. The last time that the UN's Convention on Biodiversity met, in 2014, gene drive was still purely theoretical. Since then, it has been successfully tested in yeast, fruit flies and mosquitoes.
Historically, even if scientists accidentally released some kind of horrible mutant man-eating fruit fly into the wild, after a few generations of breeding Mother Nature would eventually kill off those mutant traits. If this man-eating fly mated with a wild fruit fly, natural selection would likely weed out that man-eating gene in favour of a dietary preference that has over time evolved to help the fly best survive its natural habitat. The gene drive, though could, override nature's emergency brakes and go full-speed ahead filling the world with flesh-eating pests.
"The fast-moving nature of this field is both encouraging and a point of concern," the federal National Academies of Sciences said earlier this year in a report assessing the risks of gene drive technology.
The report, like the UN, asked that scientists take heed of "social, environmental, legal, and ethical considerations" to develop the technology responsibly. But it ultimately concluded that the potential benefits are too great to not proceed with "carefully controlled field trials."
Environmental groups are concerned that scientists may go ahead with field trials before understanding the potential risks of gene drive. Scientists, on the other hand, are concerned that we may never understand the full benefits or risks of gene drive if research were to grind to a halt.
The middle ground, it seems, is greater transparency.
"If we're going to develop proper safeguards for gene drives or other powerful technologies," Kevin Esvelt wrote earlier this year in Nature, "we need to fix a greater problem: the closed-door nature of science."