Abstract:Based on the droplet digital PCR technology, a quantitative duplex droplet digital PCR detection method for genetically modified maize MON87411 was established. The results showed that only the maize MON87411 could be specifically detected by this method, with no amplification reaction being observed in other samples. In the amplification stability test, the copy number RSD of endogenous and exogenous genes in three parallel amplifications were 0.56% and 3.93%, respectively, which met the requirement of RSD less than 25%.The linear correlation curve showed that when the mass concentration of template DNA was between 50 ng/μL and 0.08 ng/μL, there was a good linear relationship between the copy number of target genes and the template DNA concentration, with correlation coefficients R2 greater than 0.99. The quantitative linear range of MON87411-specific gene was between 26.6 and 17 086.6 copies with the limit of quantification (LOQ) being 1.34 copies/μL. In the accuracy test, the average copy number content at the five different template DNA mass concentrations were 52.14%, 63.09%, 66.08%, 60.50% and 52.16%, respectively, which were all within the theoretical copy number content range. In summary, the quantitative duplex droplet digital PCR detection method established in this study had high specificity, good stability, wide quantification range, high sensitivity and accuracy, thus can be used for the quantitative detection of genetically modified maize MON87411.
