Abstract: An universal quantitative detection method for genetically modified (GM) soybean event MON89788 using duplex digital PCR (dPCR) with satisfying specificity, stability and sensitivity was established in this paper. This method could quantify both the endogenous and exogenous genes in a single reaction system and was demonstrated to be suitable for both droplet digital PCR (ddPCR) and chip digital PCR (cdPCR) platforms. The method then was used to qualify blind samples by a food analysis performance assessment scheme (FAPAS) test. The absolute limits of quantitation (LOQs) of ddPCR for MON89788 event-specific gene and lectin endogenous gene were 8.0 copies/μL and 8.2 copies/μL, respectively, while those of cdPCR were 7.443 copies/μL and 7.646 copies/μL, respectively. The relative LOQs of MON89788 were both 0.1% by ddPCR and cdPCR.

Key words: droplet digital PCR, chip digital PCR, GM soybean event MON89788, quantitative detection