G03022: Refinement of GMO screening methods by combining existing multiplex PCR approaches with lab-on-chip capillary electrophoresis endpoint detection
Tuesday 20 March 2007
This research project will develop rapid and simple genetically modified organism (GMO) screening methods using multiplex polymerase chain reaction (PCR) approaches and endpoint detection using lab-on-a-chip capillary electrophoresis.
Study Duration: September 2006 – February 2008
Contractor: Campden and Chorleywood Food Research Association
Background
The Food Standards Agency is the competent authority for the genetically modified (GM) food and feed Regulation (EC) 1829/2003 which lays down labelling requirements for GMOs and products containing GM material. This stipulates that any food or feed product containing a GM ingredient must declare this on the label. A threshold of 0.9% is in place for the unintentional and technically unavoidable presence of authorised GM material below which labelling is not required. Unauthorised GM food or feed is not permitted at any level.
To determine whether the labelling regulations are working in practice, it is necessary for GM deoxyribonucleic acid (DNA) detection methods in foods to be available using high throughput, low cost methodologies. Currently, PCR methods require expensive equipment, which is inaccessible to the majority of Public Analyst laboratories. This study therefore seeks to develop new DNA detection methods (or refine existing ones) for GM food that can be used as simple screening methods for enforcement work.
Research Approach
It is proposed that a lab-on-a-chip semi-quantitative Roundup Ready soya assay will be validated for use on DNA extracted from food and feed materials using a multiwell extraction instrument. In addition, multiplex assays for either 35S, NOS terminator and lectin gene, or 35S, NOS terminator and zein gene targets will be developed and tested for general screening of soya and maize materials respectively. An assessment of published multiplex assays for the identification of a number of GM maize varieties will also be undertaken. Where possible, PCR product or plasmid standards will be used for semi quantitative analysis. This will enable the results to be expressed as the percentage GM-DNA copy numbers in relation to target taxon-specific DNA copy numbers calculated in terms of haploid genomes. Finally, the full range of assays will be subjected to external trial among enforcement laboratories.