Overview on the detection, interpretation and reporting on the presence of unauthorised genetically modified materials

Unauthorised GMOs (UGM) and derived materials are not uncommon in products found on the European market. At present there is zero tolerance for UGM in the EU. In most documented cases, the UGM concentration relative to the product in which the UGM material is found, was low. Low level presence will always represent a challenge to analytically based detection, in particular if the UGM is obscured by other GM material. Sampling is related to detectability. However, the present document does not present ad hoc sampling recommendations for UGM. Analytical ad hoc implementation of the zero tolerance for particular UGMs in feed is described in Regulation EC 619/2011 (European Commission, 2011). In Europe, GM detection is predominantly achieved with polymerase chain reaction (PCR) derived methods targeting the transgenic construct and insertion site DNA sequences. The increase in number and divergence of GMOs developed and commercialised has gradually forced the GM detection laboratories to rationalise their analytical work, and most laboratories now apply initial PCR based screenings followed by (when appropriate) more specific PCR based identification and quantification. The detection of any GM is dependent on availability of suitable detection method(s) and control materials to verify the performance of the method(s). Other information, e.g. describing the novel trait, introduced genetic elements, etc. may also facilitate detection, verification and identification of the GM. For UGM, this is a major challenge, and the GMOs are therefore classified into four knowledge groups in the present document. This classification may facilitate stakeholder communication and decision making in analytical laboratories. Here it is recommended to apply the same analytical paradigm to UGM detection and detection of authorised GM. This is believed to be cost effective without resulting in unacceptably low likelihood of detection of UGM. The recommended approach is referred to as the ”Matrix approach”, and is currently implemented by many of the ENGL members. It is acknowledged that some UGMs may not be detectable with this approach, and alternative strategies are therefore briefly discussed. However, none of these alternatives are considered universally applicable but in stead represent ad hoc alternatives where available information, laboratory capacity, etc. may play key roles. A decision tree is presented, summarising the recommended principles of GM and UGM detection. Notably, the state-of-the-art of GMO analysis is not static, and it is expected that the guidelines and recommendations presented in this document will have to be modified on a regular basis. Finally, the document highlights a number of R&D priorities and points out the need for reinforced information sharing at the global level.