A powerful new technique for changing genes in insects, animals and plants holds great promise, according to a report from an influential panel of scientists released Wednesday. But the group also says it's potentially very dangerous.
As such, the report from the National Academies of Sciences, Engineering and Medicine concludes that it's far too soon to release any organisms altered with the technique, known as a gene drive, into the environment.
Even so, scientists should continue conducting experiments using this approach inside laboratories, the report urges. And the panel endorsed the possibility of conducting very controlled studies of creatures altered with a gene drive outside laboratories.
"There is insufficient evidence available at this time to support the release of gene-drive modified organisms into the environment," the report states. "However, the potential benefits of gene drives for basic and applied
research are significant and justify proceeding with laboratory research and highly-controlled field trials."
Scientists have been able to make changes in genes for decades. But the new technique would enable changes to be passed on and spread quickly through an entire species, not just an individual.
The technique involves combining new methods for making very precise changes in DNA with a gene drive, which is a sequence of DNA that can cause a genetic change to be inherited much more easily by the offspring of an organism. That can be done using a technology called CRISPR/cas-9 and other methods.
The advance is raising excitement that it could be used to help fight diseases like malaria by changing mosquitoes so that they can no longer carry the parasite. In November, scientists at the University of California created a strain of mosquitoes with a gene that blocks malaria.
The technology might also help with other insect-borne diseases such as West Nile, dengue fever, Zika and Lyme disease. Genetically modified mosquitoes are being tested as a way to control the dengue fever, chikungunya and the Zika viruses, but those mosquitoes were modified using more conventional techniques.
Gene drive technology might also be used to eradicate damaging invasive species, and potentially create crops that are far more resistant to pests.
But the approach is also raising serious concerns. The major issue is uncertainty about what would happen if scientists start to release these genetically engineered creatures from their labs. The engineered organisms could upset the delicate balance of an ecosystem, inadvertently destroying other species, causing new diseases to emerge or prompting existing illnesses to spread to new places.
Some worry that the technology could end up in the hands of bioterrorists. One fear is terrorists could use the approach to engineer insects that spread toxins or new diseases.
Because of all these concerns, the report recommends that scientists first conduct extensive studies in the laboratory before even considering any kind of field tests.
Field tests, if they were to happen, should be done very cautiously to make sure the organisms could not spread widely, the report advises. For example, they could be tested inside enclosures such as greenhouses or on isolated islands.
In addition, the panel recommends that scientists take other steps, such as making sure they can track any organisms modified this way. The also advise engineering organisms with a genetic "switch" that could be used to reverse changes.
The report was welcomed by many scientists.
Anthony James of the University of California, Irvine, one of the scientists who created the mosquitoes that can block malaria, praised the report for providing a careful framework for conducting research. "I think it's actually fair and balanced and well done," James says. "I think they did a really good job."
But the report also drew some criticism.
Kevin Esvelt, a leading gene drive researcher at the Massachusetts Institute of Technology, said the committee should have called for scientists to publicly disclose any plans to create an organism modified with a gene drive far before they even try doing so.
"The National Academy hit a lot of the right notes in terms of advice on the ethics and the ecological safety," Esvelt says. "But do we really have the right to even to build something in the laboratory when a mistake could affect the lives of people outside the lab? Do we have the right to even take that first step of building it without telling the people who might be affected? I would say the answer is no. And they did not go that far."
Jim Thomas of the ETC Group, a technology watchdog organization, said the committee should have recommended greater measures to make sure the technology is not used as a biological weapon or controlled by large agricultural companies.
"The current handful of gene drive pioneers argue that their new tool could wipe out malaria or save endangered birds," Thomas said in a statement. "However, it is clear to all that any promises by the inventors come bundled with enormous threats."
Copyright 2020 NPR. To see more, visit https://www.npr.org.
