Nov 26, 2010
11th International Symposium on the Biosafety of GMOs
New biotech breeding methods under the spotlight – closer collaboration with developing countries
This year’s International Symposium on the Biosafety of Genetically Modified Organisms (ISBGMO) took place in Buenos Aires (Argentina) from 15 to 20 November. More than 300 international researchers discussed issues including the experiences of Latin American countries in the area of biosafety research, safety aspects of GM energy crops and the use of genetically modified mosquitoes to combat the infectious diseases transmitted by these insects, such as dengue fever and malaria. A new focal point was the risk assessment of the latest generation of biotech breeding methods.
The 11th ISBGMO took place in Buenos Aires (Argentina). The next symposium will be held in two years’ time in St. Louis (USA).
Professor Nina Federoff from the Huck Institutes of the Life Sciences served as Science and Technology Advisor to the US Secretary of State until 2010. She presented new biotech methods in plant breeding and called for aggressive use to be made of them, claiming this was the only way that agriculture could be intensified to meet rising food and raw material demands without putting even more pressure on the environment.
Patrick Rüdelsheim, President (2009-2010) of the International Society for Biosafety Research (ISBR): “The symposium is intended to bring together regulators, industry representatives and biosafety researchers and to support informed decisions about the risk assessment and approval of GM crops.”
Training workshop on problem formulation: The participants discussed ways of systematically defining potential environmental risks of certain GM plants and ways of using these to develop a risk assessment. They worked through case studies in small groups.
The ISBGMO takes place every two years and is the only international conference that deals exclusively with the environmental impacts of genetically modified organisms. The current President, Patrick Rüdelsheim (Belgium), stressed the special role played by the conference, saying it was about bringing together biosafety researchers, regulators and companies that develop GMOs. “Our experience has been very good. The regulators can communicate the information they require for risk assessments from companies and basic research. The companies make use of the expert discussions to adapt their products to new safety requirements at the development stage.”
He made it clear that decisions for or against genetically modified products are made on more than purely scientific grounds. Research was there to provide the scientific data for the decision-making process. At the end of the day, genetically modified products were approved or declined in accordance with the social context. The opportunities offered by biotechnology must be weighed up against the scientific uncertainties, potential risks and possible benefit. The possibility of combating mosquitoes as carriers of diseases like malaria and dengue fever by releasing genetically modified mosquitoes was, he claimed, an example of a responsible weighing-up of innovations in bioengineering.
New breeding methods under discussion
At the ISBGMO, new biotech methods were presented that were considered by many of the participants to be important advances in plant breeding. The principle methods discussed were RNA interference and a new targeted mutation method called EXZACT
With RNA interference it is possible to disable specific genes. Short DNA segments are inserted into the plant that have a sequence that appears in the gene which is to be silenced. When the new DNA segments are expressed, they form a hairpin-shaped RNA (hpRNA) in the plant cell that uses a natural cell mechanism to prevent the target gene being expressed. This technique has already been tested successfully in the production of virus-resistant and insect-resistant plants. One example is maize that is resistant to the Western corn rootworm. This maize contains an hpRNA that targets an enzyme in the insect’s digestive tract. If the beetle eats this type of GM maize, the hpRNA in its intestine prevents it from taking in nutrients. These plants could be an alternative to the existing Bt plants, to which some pests have already developed resistance.
From the point of view of biosafety research, the RNA interference method is safe, according to Adriano Fusaro from Sidney University in Australia. In his presentation he reported that research so far has found only a few exceptional cases where RNA interference unintentionally silenced other genes as well as the target gene. Events of this kind could trigger unintended side effects in the plant metabolism. Nevertheless, Fusaro was optimistic, explaining that modern, computer-controlled sequence analysis makes it possible to use RNA interference very accurately. In addition, we now have very precise analysis methods to identify reliably any unintended gene silencing.
EXZACT is another method that can be used to silence or partially modify genes at defined points on the genome and to insert new genes. Developed by Dow AgroScience, the method is based on zinc finger nucleases. These enzymes only bind to defined sites in the genome, where they can trigger the gene modifications in question. Conventional plant-breeding methods, like mutation breeding using gamma rays or chemical substances, lead to countless gene modifications randomly distributed throughout the genome. Even with existing genetic engineering methods, it was not previously possible to define the integration site of the new genes in advance. This means that the new method could be a way of avoiding unintended metabolic changes in the breeding process, thereby speeding it up.
Focus on developing countries
Biotechnological breeding methods are increasingly attractive to developing countries as well, as a means of increasing food production. According to a survey conducted in Latin America by the International Centre for Genetic Engineering and Biotechnology (ICGEB), eleven countries in the region are currently developing genetically modified plants and thirteen are conducting field trials.
According to information from the ICGEB, however, most of these countries do not have an appropriate infrastructure, such as laboratories, local experts and personnel, to carry out their own risk assessments and approve GM plants properly. Only 36 per cent of these countries have developed functioning regulatory systems. This year’s symposium offered a chance to do something about this. To strengthen expertise in developing countries there was a training workshop for Latin America on planning and conducting field trials, an OECD workshop on environmental safety research and its harmonisation, and a workshop on the definition, problem formulation and assessment of potential risks.
Moises Burachik from the Argentinian Ministry of Agriculture highlighted a peculiarity of risk assessments of GM products in Latin America. The region has a very high level of biodiversity and a vast range of different environments. Special attention would have to be paid to this when developing and using GM plants. Although he was not convinced that GM crops endangered the environment, he believed that, in accordance with the precautionary principle, biosafety research must be further intensified to develop suitable strategies to conserve local biodiversity. These could include the use of containment methods, for instance, to prevent GM plants from outcrossing into wild populations.