Comparison of two methods for the quantitative assessment of genetically modified soybeans

Abstract Genetically modified soybean strains are trade monitoring object by China. Currently, the genetically modified soybean MON89788 has been approved in China to be imported as processing raw material. Therefore, there is an urgent need to establish a method to quantitatively assess MON89788. This study used droplet digital PCR technology to quantitatively detect MON89788. The results showed that the genomic DNA concentration and its copy number of genetically modified soybeans showed a certain linear relationship. The formula was y = 2.5967x + 3.1437, where R2 = 0.999. When the same 4.5% genetically modified sample was contained, the results of the droplet digital PCR ratio and linear methods were 5.88% and 3.599%, respectively. Comparing the two results showed that the droplet digital PCR ratio method has a larger error than the linear relationship method. The novel droplet digital PCR linear relationship method established in this study has high sensitivity and specificity, and thus is a good prospect for quantitative research.