Investigation of the use of rolling circle amplification for the detection of GM food

We describe a study on the use of rolling circle amplification (RCA) for detecting GM event-specific motifs within short PCR amplicons, synthetic oligonucleotides, and extracted plant genomic DNA targets, as an alternative to the polymerase chain reaction (PCR). PCR-based detection has limitations that include the cost of reagents and equipment, and the potential for erroneous amplification of a contaminant. Our results reveal that RCA enables discrimination between the wild type (wt) and GM motifs when the sequences are within short PCR amplicons or synthetic oligonucleotides, but not within plant genomic DNA. These findings highlight the potential problem with implying the success of an assay when illustrated using model systems, rather than with the plant genomic target DNAs. The GM motifs selected for our studies were within Roundup ReadyTM Soya (RRS) and MON810 maize. Although knowledge of the target sequence is a prerequisite for the function of this assay, the potential of using RCA is explored.