A powerful new genetic technology could eliminate scourges such as malaria and rid entire countries of destructive invasive species. But officials from the FBI to the Pentagon to the United Nations bioweapons office, STAT has learned, are concerned about the potential of “gene drives” to alter evolution in ways scientists can’t imagine, and even offer a devastating new tool to bioterrorists. Now they are scrambling to get ahead of it.
The Pentagon’s shoot-for-the-moon research-funding arm, DARPA, though enthusiastic about the potential benefits of gene drives, is studying approaches that could halt them if they went out of control and threatened ecological havoc.
A special agent from the FBI’s Weapons of Mass Destruction Directorate, which works to prevent nuclear, chemical, and biological attacks, is scheduled to brief a scientific panel in Washington next week that is advising the government on how to regulate gene drives. The bureau declined to comment on its interest in the technology.
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In advance of the panel meeting, one scientist said he was asked about a recent story in a London tabloid. This summer, the Daily Star — known for headlines like a “reality babe who flashes everything” — warned that the terrorist group ISIS is using gene drives to make “supercharged killer mosquitoes.”
Experts regard that as unlikely. But the idea that gene drives pose a biosecurity threat is anything but. Because the technology to create a gene drive is widely accessible and inexpensive, biologist Kevin Esvelt of the Wyss Institute for Biologically Inspired Engineering at Harvard University warned the scientific panel at an earlier meeting, “We have never dealt with anything like this before.”
Gene drive is a molecular technique that slips a new gene into an organism and guarantees that it will be inherited by offspring and by subsequent generations. That’s possible because gene drive not only introduces a new gene but destroys competitors of that gene. Result: even if the genetically engineered organism mates with a partner carrying a different version of the gene, all of their descendants will carry the engineered gene and express the associated trait.
Once a few organisms are genetically altered, therefore, the new trait is “driven” through a population.
That could be a godsend. Using gene drives to make locusts unable to swarm, to make invasive species unable to survive in their new home, or to make mosquito immune systems destroy the malaria parasite so they don’t transmit it to humans, are just some of the benefits scientists think the technique could bring.
But accidents are possible. A lethal gene engineered into a pest species, say, might jump (or, as biologists put it, “horizontally transfer”) into another species that’s a crucial part of an ecosystem.
“People are going to have a hard time deciding if it’s safe to introduce gene drive into a wild population,” biologist Allison Snow of the Ohio State University told an earlier meeting of the scientific advisory panel convened by the National Academy of Sciences, which provides scientific advice to the government. “You can’t always predict from a laboratory experiment what will happen in nature.”
Next week’s meeting of the panel will focus not on accidents but on the potential for intentional misuse of gene drives. Dr. Amesh Adalja, a biosecurity and infectious diseases expert at the University of Pittsburgh Medical Center, told STAT he was sent the “ISIS is making superkiller mosquitoes” story by the panel to spur his thinking. He will speak about gene drives and “entomological warfare.”
With gene drives, he said in a telephone interview, it might be possible to introduce a toxin-making gene into the salivary glands of malarial mosquitoes so that when they bite they transmit not only that disease but also something quickly lethal. The trait would quickly spread to countless mosquitoes. Or perhaps gene drives could make insects “more hospitable” to dengue or other disease-causing viruses, Adalja speculated, or enable them to expand their range, bringing malaria and other scourges to regions far from the tropics.
Such genetic engineering has been possible, in theory, for decades. What’s different is this: with earlier technologies evil scientists would have had to slip the dangerous genes into each and every egg or embryo in order to make an individual organism carry it and, probably, do that over and over as the original carriers died out or failed to pass the trait to their descendants. With gene drive, you have to do it only a few times, depending on how quickly a species reproduces. By one calculation, said the Wyss’s Esvelt, using gene drive to engineer a single mosquito out of 10,000 would cause 100 percent of them to carry the new trait within just 16 generations — mere months.
Lighting a fire
In a 2014 paper in eLife, scientists led by Esvelt and Harvard biologist George Church called for “thoughtful, inclusive, and well-informed public discussions” about gene drives. They focused on the possibility of well-intentioned uses of gene drives going bad, bringing “unwanted ecological effects” by, for instance, driving invasive species into extinction. That July, 10 scientists, in a paper in the journal Science, called for regulating gene drives, citing similar concerns.
Those warnings came before any lab had created a gene drive. When one at the University of California, San Diego, did so, reporting its breakthrough last March, suddenly a theoretical threat was one step closer to reality.
That lit a fire under not only the Academy but other expert groups, too.
The National Science Advisory Board for Biosecurity, part of NIH, provides advice to the federal government on “dual-use research of concern,” or legitimate studies that could be hijacked for bioweapons. The main focus of the biosecurity board has been on research to make pathogens such as the influenza virus more lethal or contagious. But “we’re all aware of [gene drive] and I expect it will be next up,” a member of the biosecurity board told STAT.
The UN office that oversees the Biological Weapons Convention has been briefed on gene drive, said Piers Millett, who worked there for over a decade and is now a bioweapons policy specialist at the Woodrow Wilson International Center for Scholars in Washington.
“One of my duties [at the UN bioweapons office] was horizon scanning,” Millett said. He urged the office to get up to speed on the potential bioweapons implications of gene drives.
The possibilities for “weaponizing” gene drives range from suppressing pollinators, which could destroy an entire country’s agriculture system, to giving innocuous insects the ability to carry diseases such as dengue, said MIT political scientist Kenneth Oye, who briefed the bioweapons office.
Gene drive is particularly worrisome because “it’s not just one or two labs that are capable of doing the work,” Oye said — and the “capable” could include do-it-yourself “garage biologists.”
Oye told the Academy panel, “You need to have people probing the security implications [of gene drives] much more effectively” than is now being done.