POSTED ON BEHALF OF NIKOLAY TZVETKOV
Dear Forum participants,
Once again I would like to thank you all for your contributions to the forum. There were 32 comments posted by 26 participants from 11 Parties, and 15 organisations.
With regards to the first subtopic that was under consideration for this discussion, there was a general agreement amongst participants that most, if not all, living organisms that are already developed or are currently under research and development through techniques of synthetic biology fall under the definition of living modified organisms under the Cartagena Protocol. Several participants also pointed to the link this has to the application of relevant risk assessment methodologies as per Annex III, however, seeing as our next discussion will focus on this topic I will not elaborate further on this issue.
Some examples of organisms that were developed through synthetic biology techniques that are LMOs that were provided by participants included:
• The Mycoplasma mycoides bacterium developed by the J. Craig Venter Institute which is a bacterial cell into which a synthetic genome that is different from the genome of the recipient cell. The resulting organism was found to have on all the characteristics defined by the synthesized genome.
• A Baker’s yeast or Saccharomyces cerevisiae, Sc2.0, which is being modified to redesign all 16 chromosomes in such a way that they are computationally designed and assembled using DNA synthesis and molecular biology techniques.
• Semi-synthetic (xenobiology) organisms containing an expanded genetic alphabet developed through the use of unnatural base pairs. Such organisms, at present, are based on manipulating nucleic acids.
There was some disagreement over the classification of organisms resulting from gene editing techniques and cisgenesis. Some participants were of the view that such organisms fit the definition of LMOs since they are derived through the application of modern biotechnology to produce a living organism that has a novel combination of genetic material. On the other hand, some participants were of the view that organisms developed through gene editing or total genome synthesis may contain only single or few base-pair changes which could have been obtained through traditional breeding techniques (including natural and induced mutations); in such cases, these organisms would not be LMOs. Likewise, some participants also argued that organisms developed through cisgenesis do not “overcome natural physiological reproductive or recombination barriers” as the modified genetic material originates from the recipient organism itself; following the same logic, an organism developed through cisgenesis would be an LMO if it contained any novel combination of genetic material that could not be obtained through natural recombination or traditional breeding (for example, a piece of foreign DNA such as a transcription terminator or vector backbone).
Several participants also highlighted some examples of grey areas of synthetic biology research where the resulting outcome may need to be monitored as they are developed due to their potential impact on biological diversity and, in some cases to determine whether or not they fit the definition of an LMO as per the Cartagena Protocol once they are developed. Such examples include:
• The development of artificial self-replicating cells, or protocells. While there is research being conducted in this area there are currently no examples of self-replicating protocells. In addition, most of the research groups working in this area are exploring protocells based on nucleic acids, which if successful, may therefore also be considered an LMO under the Cartagena Protocol.
• The development of cell-free systems for protein synthesis. Such systems may have implications at two levels; the first is the possibility that from such a system viable organisms may emerge, e.g. when used to pack genetic elements into viral particles.. Secondly, such cell-free systems may use genetic resources and “bioparts” and potentially be scaled up to produce compounds that could replace naturally sourced products thereby impacting sustainable use and equitable sharing of benefits from biodiversity.
• Use of manipulations that do not lead to a “novel combination of genetic material”, such as, the injection or spraying of functional RNA/ DNA molecules for vaccination, immunotherapy or agricultural pathogen control;
• Use of techniques that do not involve “in vitro nucleic acid techniques” such as supplementation-based incorporation of non-canonical amino acids at the protein level where, for example, a microorganism is starved of a specific natural amino acid, forcing the organism to incorporate a structurally similar synthetic amino acid into its proteins instead.
• Organisms that have been modified through epigenetic engineering, such as histone modification and DNA methylation, for the purpose of altering gene expression. Such organisms may have altered biological properties without having “a novel combination of genetic material” if the term “genetic material” is strictly understood to refer to changes in the sequence of nucleic acids.
In an attempt to facilitate the consideration of our discussion by the AHTEG, I attempted to develop a table comparing the different types of organisms and techniques mentioned against each of the criteria in the definition of an LMO. The table is attached to this message and can be viewed here https://bch.cbd.int/cms/ui/forums/attachment.aspx?id=1414
With regards to the second subtopic that was under consideration for this discussion, namely evaluating the availability of tools to detect and monitor the organisms, components and products of synthetic biology, participants shared views on a number of issues.
Some participants pointed to some common methods that may be useful in detecting and monitoring organisms of synthetic biology that target the modified DNA sequences through PCR based amplification. Several participants pointed to the difficulties that may be faced with LMOs that may have been produced through gene editing, cisgenesis or genome synthesis and as such may not have a suitable target marker due to the changes being indistinguishable from naturally occurring counterparts. Suggestions for the inclusion of a suitable marker gene or “watermark” were made by some participants.
With regards to detecting products of synthetic biology, it was highlighted that this may also be possible through the application of analytical chemistry techniques that may be able to distinguish between products of synthetic biology and naturally occurring or chemically synthesised counterparts by detecting for the presence of other substances that will vary depending of the source.
On the other hand, several participants were of the opinion that no statements can be made about monitoring tools at this stage because the need for such tools would be dependent on the properties of the organism in question. Any monitoring measures would be put in place as part of a risk analysis performed on a case-by-case basis as an outcome of assessing the risk of a particular organism. These participants were of the view that the need for monitoring tools cannot be discussed in a generic manner.
Once again I want to thank all of you who made contributions to those two topics and I believe that your efforts will greatly facilitate the discussions at the coming AHTEG meeting and the work on modern biotechnology under CBD and its Protocols in general.