Recently in China, scientists genetically engineered a beagle to double its muscle mass. The scientists juiced up the aptly named Hercules by “editing” a gene called myostatin. While scientists have been able to edit genes for some time, the advent of a powerful tool called CRISPR has made gene editing — the insertion, deletion or modification of a gene in an organism — easier, cheaper and more precise. Although the case of the super-beagle raises potential ethical considerations related to the implications of inducing such dramatic changes in an animal, it also points to a broader set of issues that merit wider attention.
These broader issues stem from a particularly potent use of CRISPR: so-called gene drives. In classic Mendelian genetics, an individual organism has a 50-50 chance of inheriting a gene. But gene drives using CRISPR can nearly guarantee that an edited gene will be passed on to an organism’s offspring. In effect, CRISPR offers a tool that can bias inheritance, thus helping to ensure that a gene will be spread through a given population.
Gene drives represent a game changer in the field of genetic engineering. Their use is relatively cheap, and because CRISPR introduces edits at specific locations within targeted genomes in a way that is unprecedented in its ease of use and accuracy, it is becoming increasingly accessible — there is even talk of teaching the technique to high school students. Researchers are already exploring how this tool could be used in non-human organisms, such as driving a gene through malaria-carrying mosquito populations, effectively rendering them extinct and possibly eradicating the disease. Given the terrible toll that malaria takes on the world’s most vulnerable, and the predicted expansion of malaria zones in a warming world, it is no wonder scientists hold great hope that gene drives could present a new approach to tackling vector-borne diseases.
We believe that the potential for applications like these provides a morally compelling argument for committing to this new research agenda. At the same time, however, we need to watch out for possible hazards and take appropriate precautions, especially when research moves into the field. For example, the ecological effects of eliminating a whole species of mosquitoes are unknown.
The scientific community engaged in this research is developing ways to potentially mitigate or reverse unintended harmful effects of particular gene drives. Nonetheless, we need to carefully consider the possibility of irreversible ecological damage. This is especially worrisome when it comes to “dual-use concerns” — essentially the possibility that gene drives could be used for both peaceful and military purposes, such as driving a harmful gene through a country’s food crops. There are numerous examples of good technology being used badly and little reason to think gene drives would be an exception.
Although the use of gene drives in the field may still be years away, it is imperative that we begin considering these issues now. A good sign that the scientific community is taking concerns such as these seriously is the organization by the National Academy of Sciences of a Committee on Gene Drive Research in Non-Human Organisms. We addressed the committee in October, as part of its broader effort to produce a study on the science, oversight, governance and ethics of gene drive research.
We recommend that a serious consideration of the ethical implications of gene drive research address at least three issues.
— First, as suggested above, we need to find the right balance between the potential benefits that any specific application of gene drive research could produce and the real risk of unintended negative outcomes. Such assessments must be taken up case-by-case. A blanket condemnation or celebration of this technology risks denying communities the possible benefits of this work on the one hand, or recklessly ignoring the possible pitfalls on the other. These include the risks of irreversible ecological effects and harm to human health and well-being.
— Second, we need to develop, as soon as possible and at a minimum, voluntary guidelines for responsible research, and possibly a full stakeholder process to consider regulation of different stages of research and development of the technology.
— Finally, we need a process to address prevention and mitigation strategies for intentional misuse of gene drives. The prospect of a new tool in the bioterrorist’s arsenal is cause for concern. Fortunately, though, there are examples of how such worries have been addressed in other arenas of scientific research, such as microbiology.
There is undoubtedly reason for optimism about the potential benefits that gene drives present for more effective delivery of global public goods, especially for public health. But development of these solutions must be done responsibly, considering both the potential benefits and the risks. While there are signs that the U.S. scientific community is carefully considering these risks, we must continue to press for the widest possible participation in this conversation, wherever this research is taking place.
Jesse Kirkpatrick is assistant director and Andrew Light is director of the Institute for Philosophy and Public Policy at George Mason University.