Abstract: Transgenic event-specific primers and Taqman probes based on the left-flanking sequence of 59122 were designed, and a real-time PCR method was developed to quantitatively detect the event-specific genetically modified maize 59122. The standard reference molecule (integration of the reference gene sequence and the left-wing sequence) with a gradient range of 101－105 and a quantitative range of 0.01%－100% were obtained by a recombinant PCR method. Two standard curves of the reference gene sequence and the left-wing sequence were established with acceptable CV (coefficient of variance), SD (standard deviation) and R2 (correlation coefficient). Five mixed samples with known genetically modified contents of 0.1%, 0.5%, 1%, 2% and 5% were determined with the results of 0.12%, 0.56%, 1.04%, 1.61% and 4.66%, respectively. The experimental error was less than 25%. The assay can be applied to analyze genetically modified content (raw materials as well as processed food) and will provide a technical support for the preparation of standard reference molecule.

Key words: event-specific, real-time PCR, genetically modified maize, standard reference molecule