Detection of Canola GMO Events Using Pentaplex Droplet Digital PCR

Abstract

Efficient detection and quantification of GMO events is necessary due to international regulatory requirements. Digital PCR (dPCR) has been widely used for detection and quantification of GMOs. The objective of this study was to detect and quantify canola GMO events using pentaplex droplet digital PCR (ddPCR) and a six-colour droplet reader. The first pentaplex qualitative ddPCR assay included three element-specific (CaMV P35S, Tnos and tE9) and two event-specific (DP73496 and MON94100) targets, and the assay was used to detect 15 canola GMO events. The second pentaplex event-specific ddPCR assay was designed for the detection and quantification of five GMO events that can be found in commercially grown canola cultivars (DP73496, GT73, RF3, MS8 and MON88302). A total of 15 canola GMO events were detected at the 0.1% level using the first pentaplex qualitative ddPCR. Specific GMO events were also detected at 0.01 and 0.05% levels. Five major canola GMO events were detected and quantified using the second event-specific pentaplex ddPCR. DNA samples spiked at 0.1, 0.5 and 1% were successfully quantified using the event-specific pentaplex ddPCR. DNA concentrations of 0.01 and 0.05% were detected with the event-specific pentaplex ddPCR. The two developed pentaplex ddPCR assays will help facilitate efficient screening and quantification of canola GMO events.