Scientists say new GMOs should not be exempted from biosafety assessments
The products of new GMO techniques cannot be assumed to be safe but must be subjected to a pre-market risk assessment tailored to the specific GMO in question, argues a new peer-reviewed analysis by scientists based in Austria, Germany, and the UK.
The key points of the analysis are:
* The characteristics of some genome editing tools, such as the small extent of the DNA sequence change or how precisely the editing tool can be targeted to a specific site, cannot be considered an indication of safety of new GMOs.
* All new GM techniques can result in unintended changes of different types and frequencies.
* New GM plants do not have a history of safe use and should not be exempted from biosafety assessments.
* The rapid development of new GM plants can compromise the detection and elimination of unintended effects.
* Existing guidance for risk assessment of GMOs as established in the EU by the European Food Safety Authority (EFSA) should be reviewed as to whether it is sufficient and appropriate for specific types of new GM applications.
* Specific guidance needs to be developed that enables risk assessors to focus their attention and resources on issues of concern specific to the different applications and that guides the assessors on how to use established and emerging tools in their assessments.
* A case-specific pre-market risk assessment should be conducted for all new GM plants, including an appropriate molecular characterisation to identify unintended changes and/or confirm the absence of unwanted transgenic sequences.
GMWatch would add that even detailed molecular analysis at a genetic level can miss some changes in biochemical composition that could affect the safety of new GM plants. So there is a need to carry out gene expression, protein and metabolite analyses to obtain a more comprehensive picture of the outcomes of the GM transformation process.
However, even these analyses could miss certain unintended compositional changes with safety implications. Thus in addition, toxicity tests in the form of long-term animal feeding studies must be carried out to ascertain the biological effects of any changes brought about by the gene-editing process and associated tissue culture processes.
Also, once commercialised, these products must be labelled in order to allow any adverse effects to be traced to the cause.
An EU perspective on biosafety considerations for plants developed by genome editing and other new genetic modification techniques (nGMs)
Michael F. Eckerstorfer, Andreas Heissenberger, Wolfram Reichenbecher, Ricarda A. Steinbrecher and Friedrich Waßmann
Front. Bioeng. Biotechnol., 5 March 2019
The question whether new genetic modification techniques (nGM) in plant development might result in non-negligible negative effects for the environment and/or health is significant for the discussion concerning their regulation. However, current knowledge to address this issue is limited for most nGMs, particularly for recently developed nGMs, like genome editing, and their newly emerging variations, e.g., base editing. This leads to uncertainties regarding the risk/safety-status of plants which are developed with a broad range of different nGMs, especially genome editing, and other nGMs such as cisgenesis, transgrafting, haploid induction or reverse breeding. A literature survey was conducted to identify plants developed by nGMs which are relevant for future agricultural use. Such nGM plants were analyzed for hazards associated either (i) with their developed traits and their use or (ii) with unintended changes resulting from the nGMs or other methods applied during breeding. Several traits are likely to become particularly relevant in the future for nGM plants, namely herbicide resistance (HR), resistance to different plant pathogens as well as modified composition, morphology, fitness (e.g., increased resistance to cold/frost, drought, or salinity) or modified reproductive characteristics. Some traits such as resistance to certain herbicides are already known from existing GM crops and their previous assessments identified issues of concern and/or risks, such as the development of herbicide resistant weeds. Other traits in nGM plants are novel; meaning they are not present in agricultural plants currently cultivated with a history of safe use, and their underlying physiological mechanisms are not yet sufficiently elucidated. Characteristics of some genome editing applications, e.g., the small extent of genomic sequence change and their higher targeting efficiency, i.e., precision, cannot be considered an indication of safety per se, especially in relation to novel traits created by such modifications. All nGMs considered here can result in unintended changes of different types and frequencies. However, the rapid development of nGM plants can compromise the detection and elimination of unintended effects. Thus, a case-specific premarket risk assessment should be conducted for nGM plants, including an appropriate molecular characterization to identify unintended changes and/or confirm the absence of unwanted transgenic sequences.