The ability to carry out gene
drives in sexually reproducing organisms bestows scientists with a powerful tool to
alter or potentially eliminate entire populations of organisms in the wild. For
example, a gene drive can be designed so that female mosquitoes express
infertility, thereby decreasing specific mosquito populations with each
generation with infertile female mosquitoes, which could reduce the spread of
mosquito-borne pathogens such as those that cause Zika, malaria, dengue, and
yellow fever.[5,6] However, this ability to rapidly alter wild populations could also
be misused, which poses novel security risks for entomological warfare,
agro-sabotage, and ecocide. For example, instead of spreading infertility in
mosquitoes, a hostile actor could spread infertility among pollinators such as
bees that are vital to a targeted country's agriculture.
If a country realizes that it has
been the target of a malicious gene drive, given time its scientists may be
able to deploy a gene drive that acts to reverse the change– a "reversal"
drive. Detection of DNA coding for a Cas9 system in a wild organism would be a
telltale sign that a drive has been released, but it is extremely doubtful that
the DNA of organisms that could be targeted– be it fish or bees– are sequenced
by scientists regularly enough to provide timely warning for the reversal drive
to take effect. A reversal drive cannot bring dead organisms back to life. By
the time it is deployed, the targeted population and the broader ecosystem it
operates within may have suffered irreparable disruption. A "reversal"
drive also cannot remove the
Cas9 component from the DNA of affected organisms, and the addition of this
component might affect the health or behavior of modified organisms. A
malicious gene drive that fails to achieve its goal, either because it was
poorly designed or rapidly reversed, will still have irreparably changed the
genetic makeup of organisms in the wild.
Developing a gene drive system,
malicious or otherwise, is not trivial. Designing an effective gene drive
requires specialized knowledge, and working with the organisms about to be
edited can be difficult. Nevertheless, engineering a CRISPR-Cas9-enabled gene
drive does not require specialized equipment. If an individual has an
institutional affiliation, suitable CRISPR-Cas9 system components can be
readily purchased from purveyors on the internet for a few hundred dollars. The
growing availability of information about these techniques and the ease with
which suitable equipment needed to apply them can be obtained raises the
specter of incompetent or ill-willed persons accidentally or deliberately
releasing organisms altered with gene drive systems into the environment.
The extent of the security
threats posed by the developments in gene drive systems remains contested
amongst experts, but the BWC is the appropriate international forum for this
discussion. Although the potential for malicious gene drives has been briefly
raised before at recent BWC meetings, the current conference framework has failed
to produce a security risk assessment for gene drives, probably because the
conference has few mechanisms to do so. The BWC lacks a mechanism similar to
that of the Organisation for the Prohibition of Chemical Weapons' Scientific
Advisory Board, which consists of experts from many different countries who
meet to thoroughly assess and report on technology developments relevant to the
Chemical Weapons Convention. As the Eighth Review Conference proceeds, its
participants would do well to establish such a science
advisory body that
would be tasked to meet in a timely fashion to assess breakthroughs in the
biosciences with likely relevance to the operations of the BWC. Doing so would
help ensure that the BWC continues to function effectively in the future.
A. Oye, “On Regulating Gene Drives: A New Technology for Engineering Populations
in the Wild,” presentation to the Biological Weapons Convention Meeting of
Experts, Session 4: Science and Technology Developments, August 6, 2014,
Geneva, Switzerland; unog.ch/bwc/docs.
 Austin Burt, “Site-specific selfish genes as tools for
the control and genetic engineering of natural populations,” Proc. Biol. Sci. 270, no. 1518 (May 7,
2003): p. 921-928.
 Kevin M. Esvelt et al., “Concerning RNA-guided gene
drives for the alteration of wild populations,” eLife 3 (2014): p. 1-21.
 Elsa Abdoun, Émilie Rauscher, Yves Sciama, Caroline
Tourbe, “Bricoleurs du Vivant: Pour Soigner, Créer, Optimiser… Ils Ont Trouvé Leur Outil!”
[Tinkerers of the Living: To Heal, Create, Optimize… They Have Found Their
Tool!] Science & Vie magazine,
January 2016, p. 45-64.
 Andrew Hammond et al., “A CRISPR-Cas9 gene drive
system targeting female reproduction in malaria mosquito vector Anopheles gambiae,” Nature Biotechnology 34, no. 1 (January 2016): p. 78-83.
 Alternatively, genes coding for antigens against a
vector-borne disease could be inserted into the vector. Valentino M. Gantz et
al., “Highly efficient Cas9-mediated gene drive for population modification of
the malaria vector mosquito Anopheles
stephensi,” PNAS 112, no. 49
(November 23, 2015): p. E6736-E6743.
 Kenneth A. Oye et al., “Regulating Gene Drives,” Science 345, no. 6197 (August 8, 2014):
 Kevin Esvelt, “Gene Editing and Gene Drives,”
presentation to the National Academies of Sciences, Engineering, and Medicine, Gene
Drive Research on Non-Human Organisms: Recommendations for Responsible Conduct,
July 30, 2015, Washington, U.S.A.; www.youtube.com.
 The Interacademy Partnership (IAP), “The Biological
and Toxin Weapons Convention: Considerations for a Science Advisory Mechanism,”
July 2016, p.1-15; www.interacademies.net.
 Filippa Lentzos, Gregory D. Koblentz, “It’s time to
modernize the bioweapons convention,” Bulletin of the Atomic Scientists,
November 4, 2016; thebulletin.org.