A quantitative competitor PCR assay to detect genetically modified roundup-ready soybeans in commercially sold foods in Iran

Due to ever-increasing global diffusion and related socio-economic implications, the detection of genetically modified organisms (GMOs) is very important. In this study, we design a plasmid containing two genes in mutated form as construct-specific (cp4 epsps) and event specific (pd35S). It is applied for quantitative-competitor (QC) PCR as a simple and reliable method for the detection of GM food. This plasmid is calibrated with the external standard of the IRMM (The Institute for Reference Materials and Measurements), and then used to detect the presence of cp4 epsps and pd35S sequences in five foods derived from GM round-ready (RR) soya sold commercially in Iran. The results indicate the presence of GM RR soya in these products, quantitatively. In order to detect whether they contain more or less than 1% RR soya DNA, QCPCR with various amounts of DNA plasmids as a standard was performed. The results show that this plasmid can be used as a calibrator for 1% cp4 epsps and pd35S, and that it can also be applied instead of 1% IRMM genomics.