Simple, fast, reliable: multiplex digital PCR quantification of 19 genetically modified soybean events

Plant genetic engineering represents an important aspect of modern agriculture, and new genetically modified (GM) crop varieties are entering the market on a regular basis. This necessitates the development of high throughput multi-target analytical methods to detect and quantify their presence for regulatory compliance. In this study, we present a multiplex dPCR method for discriminative quantification of 19 GM soybean events and the lectin (Le1) endogene on a nanowell plate-based all-in-one dPCR system. The method consists of four 5-plex assays, taking advantage of the platform's multiple fluorescence detection channels. The assays complied with the minimum performance requirements in terms of specificity, trueness, precision, sensitivity and dynamic range, making them suitable for use in routine detection and quantification of GM crops. This method represents the most comprehensive multi-target GM soybean quantification approach to date without the need for prior screening and features a simplified workflow, making it suitable for widespread adoption. Our study sets a precedent for rapid and straightforward development of multiplex dPCR GM crop quantification assays to address the evolving demands of regulatory monitoring.