Date: September 20, 2017
Statement on the Handling of Gene Drives
Nobukazu Tanaka
Chair of Academic Association for Promotion of Genetic Studies inJapan (AAPGS)

Gene Drive is a technology for facilitating the spread of a particular genetic trait, such as amutation, which has the potential to alter the genetics of a whole population of interest in a certain
geographical area. The technical difficulty in employing Gene Drive has been overcome bycombining CRISPR/Cas9, a known genome editing technique, which has expanded the horizonof Gene Drive’s possible applications. Gene Drive technology is expected to be widely used byresearchers in various fields, particularly in studies on deliberate extinction of organisms that act
as vectors for pathogens and alien species.
On the other hand, organisms modified by Gene Drive technology (Gene Drive Organisms) havethe potential to rapidly spread certain heritable characteristics in the population of interest, in anon-Mendelian fashion. For that reason, users of these organisms must be very careful whenhandling them.
Given this background, for extensive discussions about the safety and ethically appropriate
handling of Gene Drive, a working group on Gene Drive has been established in the AAPGS.
Members of the working group have been exchanging views on Gene Drive with experts at homeand abroad, including procedures for appropriate handling of Gene Drive.
In view of the potentially significant impact of Gene Drive on the environment, the AAPGS would
like to call your attention to the following recommendations about Gene Drive:
1.

Share information on Gene Drive with all researchers at the institution:
Be aware of the debates on Gene Drive at home and abroad. The academic community isdiscussing the potential benefits and risks in using this technology. The essential first step isto share information on and relating to Gene Drive with researchers inside the institution.
Please see the Appendix for reference information.

12.

Protocols or planned experiments involving Gene Drive technology
Gene Drive is likely to be used with CRISPR/Cas9; thus, if a protocol or planned
recombinant DNA experiment describing CRISPR/Cas9 has been submitted to theinstitutional review board and use of Gene Drive is suspected from the description, theinstitution is recommended to contact the applicant to determine whether it involves GeneDrive.

3.

Be certain that appropriate containment measures are taken
As indicated above, Gene Drive Organisms have the potential to rapidly spread certain
characteristics in the population of interest. Thus, it is extremely important to takeappropriate containment measures in compliance with the Act on the Conservation andSustainable Use of Biological Diversity through Regulations on the Use of Living Modified
Organisms. If a protocol or planned experiment involving Gene Drive has been submitted,
the institutional review board at the research institution is recommended to fully confirm thatappropriate containment measures have been taken. For specific examples of containment
measures, please see the Appendix.

We recommend that all research institutions act immediately in response to this warning. Shareinformation on Gene Drive with all researchers at the institution and gather internal information
about it. Then institutional reviews of protocols or planned experiments involving Gene Drive
can be carried out appropriately.
Should you have any comments or information on Gene Drive, please contact the Secretariat ofthe AAPGS.
Thank you in advance for your understanding and cooperation in this matter.
If you have any questions regarding this communication, please contact:
Secretariat for the Academic Association for Promotion of Genetic Studies in Japan (AAPGS)
Email: aapgs@knd.biglobe.ne.jp2

Appendix

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Gene Drive

Gene Drive is a general term for a phenomenon in which inheritance of a particular genetic trait
is spread preferentially in biological populations, or the technology to accomplish this. Gene
Drive is capable of spreading a particular gene trait in non-Mendelian fashion, and thus involves
the risk of replacing a genetic trait throughout an entire population (Figure 1).
In nature, homing nuclease, meiotic drive, etc. have been observed as Gene Drive, but in recentyears, development of artificial Gene Drive with CRISPR/Cas9 has become increasingly popular.
With artificial Gene Drive, experiments using yeast, Drosophila, and mosquitos demonstrated
that targeted genetic types were modified at very high rates in laboratory populations (in the caseof Drosophila, average 97% in F2 flies). Gene Drive with CRISPR/Cas9 can be applied bypreparing a simple construct in which the host genome sequence is placed between DNAs of Cas9
and the guide RNA (Figure 2) and then introducing it into a germ cell. The elimination of technicalbarriers to the application of Gene Drive has led many researchers to explore possible applicationsof Gene Drive in search for measures against infectious diseases, solutions to agriculturalproblems, means of preserving species, etc. Thus far, Gene Drive studies on malaria-transmitting
mosquito populations have been ongoing, and there are successful reports on mosquitos that havelost the capacity to retain the malarial protozoan, and on mosquitos with artificially modified
reproductive capacity.
(This page was prepared based on the texts of Gene Drive on the Horizon, Summary, Pp1-3, 2016; Committee on Gene
Drive Research in Non-Human Organisms, The National Academic Press)3

Mendelian Inheritance

Biased Inheritance with Gene Drive

Figure 1. Schematic diagrams of inheritance: Mendel's law and Gene Drive
In non-biased heredity (Mendelian inheritance), since offspring inherit one allele from each parent(50%), preferential spread of a particular trait rarely occurs. In biased heredity with Gene Drive,theoretically, all of the offspring in a population become homozygous for the factor introducedwith Gene Drive. As a result, such a trait rapidly spreads in the population, and the whole species
can acquire that genetic trait after several generations.

HA1

Cas9gRNA

HA2

Figure 2. A construct for Gene Drive using CRISPR/Cas9
HA1 & HA2: "Homology Arm 1" and "Homology Arm 2". Sequences homologous with genome
sequences of the species of interest.
Cas9: A base sequence encoding the Cas9 protein. In use, it would be combined with a promoter
expressed in a germ cell or other specific cell.
gRNA: The base sequence of the guide RNA. The guide RNA is produced by transcription using
a promoter suitable for expressing a small RNA.

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2Containment measures

If Gene Drive Organisms escape into the environment, it would have significant impact comparedto those that general living modified organisms (LMOs) could have. Thus, when carrying out anexperiment involving Gene Drive, enhanced containment measures must be taken, compared tostandard measures required for LMOs. Also, researchers have been discussing the need ofadditional safeguards so as not to release such traits into the environment, even in the event of an
accidental escape. From this perspective, researchers should take containment measuresconforming to the Cartagena Act and the R&D Type 2 Ministerial Ordinance*, and then provide
high-level containment measures and additional safeguards suitable for the experiment orexperimental organisms involving Gene Drive.
*Cartagena Act: Act on the Conservation and Sustainable Use of Biological Diversity throughRegulations on the Use of Living Modified Organisms
R&D Type 2 Ministerial Ordinance: Ministerial Ordinance Providing Containment Measures toBe Taken in Type 2 Use of Living Modified Organisms for Research and Development[Examples of enhanced containment measures]
Facility, installation and equipment
 Installing multiple doors, air curtains, and/or an airlock.
 Using containment by air flow devices such as blast air fans or air showers.
 Filters for air conditioning equipment and air vents.
 Multiplexed containers or devices for holding organisms.
 Place containers for holding organisms in a low-temperature chamber.
 Surrounding containers for holding organisms with mineral oil or adhesive sheets.
 Keeping pesticides in the lab.
 Lab coats, shoes, etc. dedicated to the Gene Drive laboratory.
 Containers holding Gene Drive Organisms should be so labeled.
 Posting a sign saying "Gene Drive Experiment in Progress" outside a room while
implementing a Gene Drive experiment.
Considerations for implementing Gene Drive experiments
 Prohibit the entry of all personnel other than authorized personnel during Gene Driveexperiments.
 Wear lab coats, shoes, etc. dedicated to the Gene Drive laboratory, and remove them at theend of the experiment (to prevent inadvertent transfers of seeds or insects out of thelaboratory).

5 Never conduct a Gene Drive experiment concurrently with other experiments.
 Permit only skilled, experienced persons perform Gene Drive experiment.
 Keep Gene Drive Organisms separated from other organisms while holding.
 Inactivate or anesthetize organisms before taking them out of holding containers.
 Manage the number of Gene Drive Organisms depending on their characteristics (e.g., thenumber of mice kept in the cage, the number of vials if yeasts or Drosophila, etc.).
 Keep detailed records of the experiment.
[Examples of additional safeguards]
The following measures may be taken to enhance containment:
Category

What to consider

ExamplesGeneticengineeringtechnique Arrange the Cas9 and gRNA
sequences in different loci.
 Use a GFP gene sequence as the targetof Cas9.
 Regulate expression of Cas9 by the"inducible promoter + Cas9" cassette.
 Regulate activity of Cas9 with antiCas9 antibodies or Cas9 inhibitory
proteins.
 Use Drosophila with abnormal
chromosomes.
 Carry out experiments on Aedes
aegypti (dengue mosquito) in Sapporo
during the winter.
 Carry out experiments with marine
fish in an inland area.
 Carry out experiments in an isolated
place (such as an isolated island)

Geography

3Place genetic factors needed in Gene
Drive in different loci.
Use a sequence that does not exist in wild
types as a target of RNA-dependentnuclease.
Use a promoter to regulate expression ofRNA-dependent nuclease
Make use of a factor inhibiting Gene
Drive.
Designorganisms
incapableofexchanging genes with wild organisms.
Carry out experiment in a facility locatedin an environment (including climate,season) where the organisms cannot live.
Carry out experiments in an area wherewild species capable of crossing with theorganisms do not exist.
Carry out experiments in places that canlimit possible spread, even if theorganisms escape into the environment.

References
Esvelt et al., 2014. Concerning RNA-guided gene drives for the alteration of wild
populations. eLife e03401.
Gantz and Bier., 2015. The mutagenic chain reaction: A method for converting heterozygous
to homozygous mutations. Science 348(6233): 442-444.
Oye et al., 2014. Regulating gene drives: Regulatory gaps must be filled before gene drives
could be used in the wild. Science 345: 626-628.
Akbari et Al., 2015. Safeguarding gene drive experiments in the laboratory. Science349(6251):927-929.
Committee on Gene Drive Research in Non-Human Organisms. 2016. Gene Drive on theHorizon. The National Academic Press

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