A multiplex degenerate PCR analytical approach targeting to eight genes for screening GMOs

Currently, the detection methods with lower cost and higher throughput are the major trend in screening genetically modified (GM) food or feed before specific identification. In this study, we developed a quadruplex degenerate PCR screening approach for more than 90 approved GMO events. This assay is consisted of four PCR systems targeting on nine DNA sequences from eight trait genes widely introduced into GMOs, such as CP4-EPSPS derived from Acetobacterium tumefaciens sp. strain CP4, phosphinothricin acetyltransferase gene derived from Streptomyces hygroscopicus (bar) and Streptomyces viridochromogenes (pat), and Cry1Ab, Cry1Ac, Cry1A(b/c), mCry3A, and Cry3Bb1 derived from Bacillus thuringiensis. The quadruplex degenerate PCR assay offers high specificity and sensitivity with the absolute limit of detection (LOD) of approximate 80 target copies. Furthermore, the applicability of the quadruplex PCR assay was confirmed by screening either several artificially prepared samples or samples of Grain Inspection, Packers and Stockyards Administration (GIPSA) proficiency program.