EFSA is carrying out an increasing number of assessments on the safety of plants containing more than one genetic modification. The combination of two or more modifications within one plant is called a stack. Such a plant does not represent a new genetic modification. The plant contains several existing genetic modifications that have been combined through conventional breeding techniques. The aim is to benefit from the combination in one single plant of several properties created by the individual genetic modifications, such as insect resistance and herbicide tolerance.
In the international context, the European Union applies some of the most rigorous standards in the world when assessing the safety of plants containing multiple genetic modifications.
EFSA adopted its first opinion on a GM plant containing stacked properties in June 2005. As of August 2016, EFSA has adopted 28 opinions involving stacks. While most initial applications involved lower stacks with two or three genetic modifications, EFSA now assesses the safety also of higher stacks with four, five or six modifications combined in one plant.
Risk assessment of stacks
When assessing the safety of a stack for humans, animals and the environment, EFSA considers the quality and quantity of all available information and draws on the existing risk assessments of each of the individual genetic modifications that form the stack. EFSA also takes into account the data for the stack, focusing on the levels of newly expressed proteins, the stability of the modifications and on potential interactions between individual modifications combined in the stack.
The safety assessment of the GM stack plant includes all possible sub-combinations of the individual modifications. Some may have been assessed previously as separate stacks; others do not exist and data are therefore not available. In such cases, EFSA performs its assessment on a weight-of-evidence approach, using available information from risk assessments of the high stack, the single genetic modifications and existing sub-combinations to conclude on its safety.
EFSA clearly identifies any uncertainties stemming from the lack of data and, if relevant, recommends mitigation measures. For example, such measures could require applicants to provide relevant data for a risk assessment of the respective sub-combination should they produce plants with previously non-existent sub-combinations through conventional breeding.
EFSA is currently updating guidance on allergenicity to reflect scientific advances in the field. The update is based in part on extensive literature reviews, which revealed new methodologies that could be applied in allergenicity assessment. It also reflects recent EU legislation on GM food and feed by addressing new requirements for the authorisation of GM plants for the European market.
The draft guidance on allergenicity assessment of GM plants is a milestone in EFSA’s efforts to engage stakeholders in its scientific processes. An eight-member stakeholder focus group acted as a consultative body and contributed to the development of the document from the start. The involvement of stakeholders allowed EFSA to benefit from relevant expertise throughout the development of the guidance.
Guidance clarifying data requirements for GM plant risk assessment
In June 2015, EFSA published new guidance clarifying the data needs for the agronomic and phenotypic characterisation of GM plants. The document complements existing guidance on data requirements for the risk assessment of GM plants. It gives applicants seeking market approval for a GM plant in the European Union recommendations on how to generate, analyse and interpret agronomic and phenotypic data of the GM plant.
Guidance for renewal application of GMOs
In June 2015, EFSA issued a new guidance document on the information that companies need to provide when applying for renewed authorisation to import GM plants for food and feed into the European Union. The European Commission grants authorisations to place GM food and feed on the European market for a period of ten years.
New plant breeding techniques
Following a request from the Commission, EFSA launched a project in 2011 to evaluate eight new plant breeding techniques. The GMO Panel was asked to assess whether the current guidance documents would still be applicable to plants developed using these novel methods. The techniques earmarked for evaluation included intragenesis, cisgenesis and zinc finger nuclease technique (ZFN).
EFSA delivered the first of these opinions on cisgenesis and intragenesis in January 2012 followed by a second opinion on zinc finger nuclease 3 (ZFN-3) in October 2012. The GMO Panel concluded in both opinions that current risk assessment guidance (including environmental risk assessment guidance) was applicable to evaluate food and feed derived from these new techniques. In 2013, the European Commission requested that EFSA put further assessments of new plant breeding techniques on hold to allow the GMO Panel to focus on the evaluation of GMO applications and the development of guidance documents.