EFSA organised an international scientific workshop in June 2014 to discuss potential risks associated with ribonucleic acid interference (RNAi)-based genetically modified (GM) plants and to identify issues unique to their risk assessment. During the workshop, the molecular biology underlying the RNAi mechanism, current and future applications of RNAi-based GM plants, and risk assessment aspects were discussed in details. The report of that event, including summaries of presentations and discussions, is now published on the EFSA website
The workshop drew over 100 scientists and risk assessment experts from academia, risk evaluation bodies, non-governmental organisations and the private sector. Over two days, specialists from four continents shared expertise and debated the latest science on RNAi in plants, mammals and invertebrates, explored current and future RNAi applications and evaluated risk assessment considerations in light of the development of the technique.
Ribonucleic acid (RNA) acts as the body’s messenger by carrying genetic information to the part of a cell that makes proteins – key building blocks of life. RNAi is a natural process that blocks or interferes with this activity in animals and plants. In the late 1990s, scientists discovered how to use this mechanism to control the flow of genetic information.
Elisabeth Waigmann, who heads EFSA’s work on GMOs, highlights the importance for the scientific community of such an international workshop on this challenging topic.
EW: EFSA organised the event as a proactive step to assess whether the technique will affect its present approach for risk assessment of GMOs. During the discussions, participants raised relevant aspects associated to the technique or its implications on the risk assessment that will be considered with much attention by EFSA. I would therefore like to thank the participants for their active contributions.
EFSA’s team of scientists at the workshop also included members of its GMO Panel. Professor Patrick du Jardin and Dr Salvatore Arpaia were leading the discussions on specific areas of risk assessment. They give their opinion on the significance of the RNAi technique and assess the importance of the international workshop.
Q: Why is the development of RNAi significant?
SA: RNAi represents an important biological mechanism that will likely be commonly used to achieve pest resistance in next generation of genetically modified plants.
PdJ: So far, conferring new traits to plants by GM technology has mainly involved the expression of new proteins encoded by so-called transgenes. Many questions addressing potential risks to health and the environment are related to these newly expressed proteins and the current risk assessment framework may be challenged by other approaches of genetic modification like RNAi. In this approach, small RNAs - not proteins - are produced from a piece of DNA introduced in plant chromosomes, which aim at repressing the expression of target genes in the plants or even in pests feeding on plants.
What are the challenges for risk assessment associated with RNAi?
PdJ: RNAi raises new questions for risk assessment. For instance, how exactly are these small RNAs produced from the introduced piece of DNA, how do they move into and out of the plant and how stable are they in different compartments of the plant and the environment?
SA: The mode of action of the RNAi technique will pose challenging questions to both risk assessors and risk managers.
Q: What are the main achievements to come from the workshop?
PdJ: The workshop provided an unprecedented opportunity for bridging the gap between the best scientific knowledge in this area and the current practices of GMO risk assessment. New areas of concern and possible limitations of the existing risk assessment of GM plants were debated during the event.
SA: The workshop was a unique and timely occasion for hearing from worldwide experts, regulatory bodies and companies on how they perceive risk assessment of these GM plants. I think the event was a great achievement thanks to the active contributions of the excellent speakers and all participants.
Dr Waigmann reflected on the fruitful discussions and valuable insights from all participants in contributing to the success and potential impact of the event.
EW: This workshop will help inform the Authority’s risk assessment approach to an emerging technique that may lead to the development of the next generation of GMOs.