There is no doubt that ethical questions and their public discourse especially come into play when talking about genetically modified organism. In a field of research that has tremendous potential to impact our society, figuring out what is right and what is wrong can sometimes be difficult. Therefore we tried to involve as many people - experts, greenhorns, academics and business people alike - in the ethical evaluation of our project.
An opportunity for a collaboration
This is where the Bordeaux team comes in to play as their project shares some similarities with ours. Therefore the ethical questions and challenges they face are overlap with ours. As they are in contact with a number of French experts in the field of GMO and even organised a conference on the subject of ethics, meeting with the Bordeaux team should be very valuable.
In order to prepare for the meeting with the Bordeaux team we started out by reading introductory papers on the field of ethics related to microbiology. Especially the ethics handbook written by the 2017 Israelian team from Technion was of great use, giving us an overview of the different ways of looking at the “badness” or “goodness” of actions.(1) Should we only look at the consequences or just at the intention or justification? Members of the Bordeaux team pointed us to the Asilomar Conference on Recombinant DNA, held in 1975, where for the first time international guidelines on the safety of recombinant DNA were drawn up. Besides reading up on ethics we made a whole list of questions to ask to both the Bordeaux team and to the experts they have been in contact in with.
Armed with proper background knowledge and a document full of questions we set out to collaborate. The Bordeaux team kicked of the meeting with a presentation on what the term GMO entails, and which ethical issues GMOs raises. They then continued presenting about the conferences they organised, the experts they met and their findings on human practices so far. Besides just presenting the findings of their meetings with experts they also offered to bring us into contact with them.
The expert that seemed most valuable to us was Manguene Marc of the fondation Anthony Mainguéné. He and his foundation promote the responsible and forward-looking raising of awareness in innovative and creative ways. We asked the Bordeaux team to forward our most important questions to him. We also gave presentation´s to each other and a brainstorm session about ethical matters involved with the use of GMOs where we discussed the questions we prepared in advance. We summarize the findings below:
Ethical issues concerning safety can entail large questions such as how big should the risk be before we ban further work, or in other words, what is the red line? These are the kind of questions scientists have tried to answer on large scale conferences such as the asilomar conference mentioned above. For our project we looked at the more concrete and smaller safety issues directly related to our project.
One of the biggest safety concerns in most projects involving GMOs is the risk of a GMO escaping the lab. What happens when such a leak occurs? There are a number of possible consequences, including the spread of new pathogenic strains and the release of toxic molecules in the environment, and the possibility of the escaped strain taking over an existing niche or creating of a new one. How do we tackle this issue? In theory the organism we modify could live outside of the lab as s.cerevisiae is a ubiquitous. In the wild our strain however doesn't stand a chance as every wildtype microorganism will grow much faster and will likely outcompete our strain. Also there is no existing biological niche that our organism could occupy as cellulose in complete absence of glucose monomers or other carbohydrates. A future step of our strains development is inducing a tryptophan deficiency that would further limit its potential to proliferate outside of the laboratory. Besides this we’re working on methods to make our cells grow only in very specific circumstances to limit the chance of it being able to live and procreate outside if the lab. A way to really force this is by implementing a kill switch, make sure the cell can only live when a certain compound is around. This particular compound will be fed to the cell when it’s safely contained in the lab, but it won’t be able to find it when it’s out in the wild. The environmental dangers are thus very small, but this is something we should verify with more experiments and definitely not just wave aside.
Another danger of GMOs is to the people doing research with the cells, or the people processing the styrene we produce? Saccharomyces cerevisiae can be an opportunistic pathogen.(2) It could develop to be more dangerous as the human immune system has never been exposed to this novel pathogen which probably also has some antibiotic resistance genes for selective pressure. This is something that can only be limited through proper planning of the experiments and good laboratory practices. The biological danger to the people using our styrene however is zero as our production process sterilizes the product in the workup. Besides the biological dangers we also have to think about the chemical dangers as well, styrene is a molecule and exposure to it should be limited.(2) This highlights that we will have to think carefully about the safety precautions taken both in the lab both on handling the microorganisms as well as when working with and the molecules we produce.
Another thing that came up quite often during the discussions we had was public acceptance, and the importance of telling the public about what we are doing in the lab. There seems to be at least some hesitation in the public about the usage of GMOs for production of food and materials. At least part of this hesitation might stem from not knowing exactly what a GMO entails. An example that nicely illustrates this is is that when we tell people about our project, even naming that we are using modified yeast cells, they are positive, but as soon as we drop the word GMO there are people that are directly less assured of our project. We also noticed this during our various outreach events, a lot of people we talked to appeared a lot less negative towards GMOs after explaining what a GMO exactly is. We therefore deem it an import part of iGEM to tell the public of our project and hope to contribute in that way to getting rid of the ‘bad’ name of GMO’s. Important to realise here is that not all hesitance about GMO’s stems from ignorance, if people have objections because of for instance personal beliefs or religion, than that is completely valid as well.
Feasibility of using bio streams
Is it ethically fine to use already used waste streams for producing plastics? Most cellulose containing waste streams are already in use, for instance foodstock and bioethanol. Our yeast strain will be competing with the people and companies who currently use those waste streams. We will make plastics, something that possibly benefits the environment less than the current uses of cellulosic waste. It will definitely be very valuable to look into waste streams that are not already in use. We did this in a concrete way by talking to companies that process cellulose containing waste such as KNN cellulose who make recell: recycled toilet paper. Furthermore we will have to look into how beneficial it is to make plastic from cellulose compared to making it from fossil fuels. One of the ways we did this is by performing a carbon footprint analysis.
Breaking down cellulose with or without yeast?
One of the biggest difference between our project and the one of Bordeaux is the way in which we turn cellulose into glucose. We use our yeast cells for both the conversion of cellulose to glucose and the conversion of glucose to styrene while the Bordeaux team plans to perform the first step in a chemical way and only do the conversion from glucose to plastic with their micro-organism. It will be very interesting to compare which way is more optimal and efficient, not only by looking at the yield but also at the byproducts and the effects of the environment. While in order to completely weight all positive and negative sides of both strategies we need more experimental results there are already some things we can hypothesize about.
The chemical way, using acid hydrolysis, will entail using dangerous chemicals, however acid hydrolysis is is a process that’s used widely and can be done in a large reactor. There will be a byproduct consisting of polluted acid, which could potentially be reused, but this is something the Bordeaux team will have to look into. In contrast, our enzyme complex won’t have any dangerous byproducts as it just uses water. The efficiency of the enzyme complex will however likely be a lot lower than using acid hydrolysis. Furthermore we will have to take the growth medium our cells using the enzyme complex grow on into account.
 Ethics Handbook by iGEM Technion 2017: https://2017.igem.org/Team:TECHNION-ISRAEL/ethics
 Pérez-Torrado, R., & Querol, A. (2016). Opportunistic Strains of Saccharomyces cerevisiae: A Potential Risk Sold in Food Products. Frontiers In Microbiology, 6. doi: 10.3389/fmicb.2015.01522
 Leibman, K. (1975). Metabolism and Toxicity of Styrene. Environmental Health Perspectives, 11, 115. doi: 10.2307/3428333