Team:Michigan/Silver
Human Practices - Silver
Our team wanted to design a safety mechanism that could be utilized in modified organisms to minimize unintended consequences.The consequences of engineered organisms include both the ecological impacts and the effects on public perception of the organism and synthetic biology. We considered the relationship between safety and public impressions during our public engagement and education. Our human practices efforts focused on how we could create a genetically encoded containment mechanism that improved the safety of synthetic biology designs while initiating a dialogue with community members.
As we began thinking about a safety project, our research into containment mechanisms for engineered microorganisms led us to consider genetic kill switches because of their flexibility and ease of use compared to other containment methods. These kill switches are within the modified microbe and are designed to kill it outside of a defined place, time, or function. Parallel genetically encoded containment mechanisms not only offer the chance for flexibility but also reduce the risk of escape below the acceptable level of 1 escapee per 10^8. That knowledge informed our design for a temperature dependent kill switch as a new type of containment mechanism that can be used as an additional layer of control in combination with other kill switches.
Concerned about how the public views genetically modified organisms, we created a panel discussion to create a dialogue with experts and the public. That led us to consider how kill switches might be viewed by members of the public. While a kill switch that meets acceptable guidelines may be attractive to scientists and regulatory bodies, it might not be understood or favored by the general public. We developed a series of initiatives to increase awareness of synthetic biology in our own community and make our research more accessible to interested people who are not involved in research labs.
Read more about our efforts in community outreach: Education and Public Engagement
We transitioned to thinking about a framework for genetically encoded kill switches. Many iGEM teams use such safety mechanisms, but careful characterization needs to be done for each kill switch. In addition, a standardized risk assessment, such as the one suggested by a review on genetic containment mechanisms (Moe-Behrens et al. 2013) might improve the way kill switches are implemented. When iGEM teams, research groups, or biotechnology efforts adopt a kill switch, it often leads to a sense of security that may not be warranted. While well intentioned, these kill switches are often developed without public input, and do not take into consideration valid concerns about the use of engineered microbes. We propose a framework to help iGEM teams consider adopting a kill switch or multiple containment mechanisms.
11 watch dog organizations have called for a halt to any synthetic biology research (Moe-Behrens et al. 2013). While their views are not necessarily indicative of the views of most people, they do illustrate perceptions of the dangers of synthetic biology. For synthetic biology to create viable solutions, the safety of modified organisms must be demonstrated. While industry containment methods often include chemical and physical methods of killing engineered microbes, additional containment mechanisms are needed for microbes which are placed outside of the research or industrial settings. Genetic kill switches have emerged as a possible method of containing modified organisms. Other possible solutions include making microbes dependent on synthetic nutrients, or on essential organic components such as amino acids or nucleic acids. However, these containment mechanisms require large scale genomic changes and might not be feasible in organisms whose genomes are not as easily modified as that of E.coli (Schmidt and de Lorenzo 2012 ). Our team wanted to create and characterize a new type of kill switch to increase the variety of safety mechanisms that could be adopted for particular applications.
Since kill switches are widely employed by iGEM teams, other iGEM teams have previously examined genetic kill switches to determine their utility. The 2016 Marburg team concluded that extensive validation needs to be done because inactivating mutations could allow bacteria to escape control. The team recommended that other teams use parallel systems that encode kill switches to reduce the risk of escape (Marburg “Human Practices”). The UT-Tokyo team also considered the feasibility of a kill switch mechanism, also noting that each team needs to carefully consider any containment mechanisms they adopt due to the risk of mutations or horizontal gene transfer (Tokyo “Human Practices”). They referenced the Catagena protocol on living modified organisms, which focuses on the impacts of such LMOs on biodiversity (“The Cartagena Protocol on Biosafety”).
These previous iGEM teams and research articles discuss the ways in which genetic containment could be inadequate if engineered microbes are placed in environmental settings or introduced near human beings. As discussed earlier, genome recoding for dependence on synthetic molecules such as nonstandard amino acids represents another method of containment, and has demonstrated the lowest frequency of escape (Mandell et al. 2015) (Lajoie et al. 2015). However, it requires significant time and effort, making it much more difficult to incorporate in organisms that are not as well studied as E. coli (Schmidt and de Lorenzo 2012 ). For groups without tremendous resources, or those wishing to work with alternate organisms, another solution is required. As team Marburg suggested, parallel containment systems may offer flexibility and feasibility while still maintaining a rate of escape lower than the acceptable 1 per 10^8 cells (Wilson 1993). Our team hoped to introduce a new type of kill switch, and settled on a temperature dependent mechanism of regulation that would kill microbes outside of a narrow temperature range around 37 degrees Celsius. To our knowledge, no other iGEM team has made temperature a factor for their kill switch.
We created an Experiment.com page that allowed any interested people with internet access to view our project design and rationale. In addition, crowdfunding let anyone donate to our project if they supported the idea and had the means to do so. After our lab work was over, sharing our lab notebook with patrons helped to make our efforts more transparent. We also set up a panel to create a dialogue on genetically modified organisms. One professor who studies risk assessment discussed the response of members of the public to engineered microbes. He explained that, when someone does not know much about a subject, he or she magnifies risks associated with that topic. In addition, the term synthetic biology and its rapid rise in usage in recent years increases its sense of immediacy and risk. Another professor, an anthropologist who examines the response to GMO crops in India, explained how genetic engineering efforts are often viewed as part of industrial- and capital-intensive methods of agriculture.
Our project has shown potential for success, but still requires a great deal of characterization and modification to robustly control bacteria outside of the desired temperature range. Our kill switch needs further work before it can ensure a safe and desirable level of containment, so our team was forced to pause.
Following the GMO panel and coming across barriers in our wet lab work, we began to ask ourselves questions regarding our project. Is a good kill switch simply one that eliminates bacteria after their function is complete or when they escape from a certain environment? Shouldn’t the ideal containment mechanism also instill a sense of confidence in people who use microbes or live near the environment in which microbes are placed? Traditional kill switches in modified microorganisms are put into place by the research group that designed the microbe for an application. A kill switch such as our own may be seen by individuals who do not conduct research as unreliable. They might not be familiar with our work and could be skeptical of a safety metric with no independent verification. Collaboration between iGEM teams takes steps toward addressing that issue, but iGEM teams could all be seen as part of an insular scientific organization. While our outreach efforts to increase understanding about genetic engineering began the process of fostering a constructive relationship with the public, we need to work towards integrating community members- and not just university professors- into our discussion of safety.
The 2013 Woodrow Wilson national survey on synthetic biology demonstrates an increased understanding of what synthetic biology entails does not necessarily lead to a more positive view of the field. Among those polled, there has been no significant change in awareness of synthetic biology from 2010 to 2013. In 2013, 15% of those polled initially stated that the risks of synthetic biology would outweigh the benefits, and 18% felt the benefits would outweigh the risks. When presented with a balanced statement on synthetic biology, those numbers changed to 33% and 24%, respectively (“Awareness & Impressions of Synthetic Biology” 2013). The majority of those surveyed in 2010 believed the federal government should regulate synthetic biology, with about a third feeling that voluntary guidelines developed by industry and the government would be best (“Awareness & Impressions of Synthetic Biology” 2010).
In 2015, a paper demonstrated that a synthetic array using CRISPR to degrade plasmid or genomic DNA could be used to kill cells and degrade specific genes (Caliando and Voigt 2015). Induction of the kill switch by arabinose could contain engineered microbes and also prevent horizontal gene transfer, as both the organism and its DNA are degraded. The last author on the paper, Dr. Voigt, stated that such a kill switch may offer a greater deal of control while also noting the difficulty in placing a modified organism outside of a controlled lab setting (Sarich). However, a website entitled Natural Society had a less favorable view of the kill switch. The author of a post on the kill switch commented that it is meant to assist corporations in controlling engineered organisms and expressed skepticism that biotechnology companies would properly characterize and implement such a kill switch, further illustrating that even those familiar with the method by which kill switches work still harbor anxieties about their responsible, safe execution. The author also stated that there is a possibility for interbreeding between organisms such as GM mosquitoes and wild populations that could alter the properties of the kill switch (Sarich). The issues raised were not with the design of the kill switch construct or its ability to cause lethality in the lab, but with implementation into the environment. While the views expressed on that website may not represent those of a majority of Americans, they are the legitimate concerns of some community members. The post also supports the point made in the 2013 poll on synthetic biology. Namely, the public would prefer federal regulations to voluntary guidelines made by research groups or industry.
Synthetic biology has focused on the possible ecological and health consequences of modified microbes persisting in the environment or interacting with other organisms. Much work has been done on containment mechanisms, and numerous reviews have noted the possible pitfalls of kill switches and discussed how they could be improved or incorporated in addition to other containment mechanisms (Wolfe et al. 2016). We believe the social and cultural context into which an organism is placed are also fundamental for development of engineered microbes. That makes it critical to develop a thorough understanding of impressions of modified organisms. Regardless of the scientific accuracy of a belief about a particular engineered microbe, those beliefs are valid to those hold them, and those beliefs can influence the impact of that organism.
This is true within the lab and industrial setting as well. A recent article on synthetic biology focused on the social and behavioral characteristics of different research groups and industrial settings have take on various levels of risk according to the necessity of the work setting (Moe-Behrens et al. 2013). Since our kill switch is currently geared towards closed, industrial settings, we wanted to learn about views of our construct in those settings. To learn more about lab culture and determine how that might affect the ways in which our kill switch could be used, we interviewed several professors and a postdoctoral researcher. Because our kill switch was still in preliminary stages, we were not able to have conversations with industry professionals or lab safety experts. Going forward, we hope to better characterize and modify our kill switch so that we can determine how it could be integrated into the culture of various industrial practices. We would also like to work with members of the University of Michigan Environment, Health & Safety department to determine how we can modify our design and anticipate the ways in which it will be used.
A thorough review of various kill switch mechanisms commented on the lack of standardized practices in evaluating kill switches. The authors called for standardized, risk-related analysis which would allow researchers to discuss the risks of their modified organisms but also allow flexibility to comment on any type of modified organism. Their example risk assessment focuses on the Woodrow Wilson group’s four focus areas for synthetic biology organisms. These focus on the ecological impact of modified organisms. The authors discuss possible ways to bring induce a vested interest in others concerning the ecological impact, mentioning briefly that a dialogue needs to be established with the public. We propose an expanded risk assessment that considers the ecological impacts and social repercussions while discussing how the modified organism might be received in the context in which it is placed. That also addresses a major concern of those surveyed, that synthetic biology is “artificial” or “unnatural”, and mentioning the specific application alters how people weight potential risks and benefits (Pauwels 2009).
We must not forget that research and engineering do not happen in a vacuum, or necessarily achieve their intended purpose without complications. The impacts on society, culture, and politics of the technologies we develop are incredibly important, and should not be forgotten. The greatest danger for those of us making strides in the lab is that we will disassociate ourselves from the greater context of the world. Frustration in the face of pushback from the general public places the blame in the wrong hands; their concerns must be our concerns, our ambitions must serve their best interests.
Caliando, Brian J., and Christopher A. Voigt. "Targeted DNA Degradation Using a CRISPR Device Stably Carried in the Host Genome." Nature Communications 6.6989 (2015): n. pag. PubMed. Web.
Hart Research Associates. Awareness & Impressions of Synthetic Biology. Rep. Synthetic Biology Project, The Woodrow Wilson International Center for Scholars. Synthetic Biology Project, 9 Sept. 2010. Web.
Hart Research Associates. Awareness & Impressions of Synthetic Biology. Rep. Synthetic Biology Project, The Woodrow Wilson International Center for Scholars. Synthetic Biology Project, 6 Mar. 2013. Web.
Haynes, Karmella A. "Synthetic Biology: Building Genetic Containment." Nature Chemical Biology 12 (2016): 55-56. Nature. Web.
Lajoie MJ, Rovner AJ, Goodman DB, Aerni HR, Haimovich AD, Kuznetsov G, Mercer JA, Wang HH, Carr PA, Mosberg JA, Rohland N, Schultz PG, Jacobson JM, Rinehart J, Church GM, Isaacs FJ. “Genomically recoded organisms expand biological functions.” Science (2013) 342: 357-360.
Mandell DJ, Lajoie MJ, Mee MT, Takeuchi R, Kuznetsov G, Norville JE, Gregg CJ, Stoddard BL, Church GM. “Biocontainment of genetically modified organisms by synthetic protein design.” Nature (2015) 518: 55-60
Moe-Behrens, Gerd H. G., Rene Davis, and Karmella A. Haynes. "Preparing Synthetic Biology for the World." Frontiers in Microbiology 4 (2013): n. pag. Web.
Osório, Joana. "Synthetic Biology: Genetic Kill Switches — a Matter of Life or Death." Nature News. Nature Publishing Group, 21 Dec. 2015. Web.
Pauwels, E. “Review of quantitative and qualitative studies on U.S. public perceptions of synthetic biology.” Syst Synth Biol 3 (2009): 37-46.
Sarich, Christina. "Scientists Unveil Genetically Modified Insects with 'Kill Switch' Genes." Natural Society. Natural Society, 08 June 2015. Web.
Schmidt, Markus, and Victor De Lorenzo. "Synthetic Constructs In/for the Environment: Managing the Interplay between Natural and Engineered Biology." FEBS Letters 586.15 (2012): 2199-206. Web.
Team:Marburg/Human Practices. N.p., n.d. Web.
Team:UT-Tokyo/Human Practices. N.p., n.d. Web.
“The Cartagena Protocol on Biosafety.” Convention on Biosafety. Updated July 16th, 2013. bch.cbd.int/protocol/text/
Wilson, D.J. “NIH guidelines for research involving recombinant DNA molecules.” Account Res. (1993): 3:177-185.
Wolfe, Amy K., Maria Fernanda Campa, Rachael A. Bergmann, Savannah C. Stelling, David J. Bjornstad, and Barry L. Shumpert. "Synthetic Biology R&D Risks: Social-Institutional Contexts Matter!" Trends in Biotechnology 34.5 (2016): 353-56. Web.
