Event-specific detection of transgenic potato AV43-6-G7 using real-time and digital PCR methods.

BACKGROUND: The isolation of unknown DNA sequences flanked by known sequences is an important task in the event-specific detection of GMOs. None of event-specific detection method was developed based on the junction sequence of an exogenous integrant in the transgenic potato AV43-6-G7.

RESULTS: The flanking sequence between the exogenous fragment and recombinant chromosome of this potato was successfully acquired through exogenous gene 5'-RACE. The event-specific primers and Taqman probe were designed to amplify fragments spanning the exogenous DNA and potato genomic DNA. The specific real-time PCR and digital PCR detection methods for AV43-6-G7 potato were established based on primers designed according to the flanking sequences. The detection limit of the qualitative PCR assay was 0.01 % for AV43-6-G7 potato in 100 ng of potato genomic DNA, corresponding to approximately 11.6 copies of the potato haploid genome. The ddPCR assays for Potato AV43-6-G7 achieved a limit of quantification of approximately 58 target copies, with RSD ≤ 25 %. The aLOQ of this system was approximately 1.2 copies.

CONCLUSIONS: These results indicated that these event-specific methods would be useful for the identification of potato AV43-6-G7.