Validation of a Real-time PCR On-Site Quantification Method for MON810 Maize

Accurate quantification of GM to ensure compliance with labelling thresholds, e.g. the EU limit of 0.9%, requires intensive sampling and stringently validated methods. This is normally targeted at bulk consignments at one of several critical stages of the food/feed chain post farm gate. However, at the field level, following introduction of GM co-existence regimes, instances may arise that pose possible breaches of co-existence rules, with the potential for high economic impact for producers if precautionary labelling is sanctioned. In such instances, a rapid on-, or near-site, quantitative method for use as a pre-harvest predictive decision tool for adventitious GM presence (AGMP) would be of use. To this end we have adapted a laboratory-based protocol for real-time quantification of the MON810 GM event in maize kernels (using Taqman� technology) for on-site testing using the portable Cepheid SmartCyclerII instrument. The duplex RT-PCR method requires a basic support infrastructure (bench, electricity, small grain mill or blender, water bath and micro-centrifuge) and can be completed in 2 hours (excluding sampling). The adapted method was pre-validated through an international ring-trial in six EU collaborating laboratories (employing only specified portable equipment). Results showed that the adapted method as performed on the portable instrument complied with minimum assay performance requirements as defined by the European Network of GMO Laboratories (RSDr = 18.5%; RSDR = 32.8; Bias = 26.7%). Coupled with an appropriate field sampling approach, this technology has the potential to form the basis of an on- or near-site predictive decision tool for pre-harvest MON810 AGMP in maize production.

JRC.DDG.J.5 - Agriculture and Life Sciences in the Economy