A universal quantification of transgenic soybean event DAS-68416-4 using duplex digital PCR

Area of Science:

• Agricultural Biotechnology
• Molecular Biology
• Genetics

Background:

• Increasing global regulations on genetically modified (GM) components necessitate precise quantification methods.
• Digital polymerase chain reaction (dPCR) offers advantages over traditional real-time fluorescence PCR for GM quantification.

Purpose of the Study:

• To establish a universal quantification method for transgenic soybean event DAS-68416-4 using duplex digital PCR.
• To evaluate the performance of dPCR for accurate detection and quantification of GM soybean components.

Main Methods:

• Development of a duplex digital PCR assay for simultaneous detection of the DAS-68416-4 event-specific gene and a reference lectin gene.
• Determination of absolute and relative limits of quantification (LOQs) using both droplet digital PCR and chip digital PCR platforms.

Main Results:

• The absolute LOQs for the DAS-68416-4 event and lectin genes were determined for both dPCR systems.
• Relative LOQs for the DAS-68416-4 percentage content were consistently 0.1% across both droplet and chip dPCR platforms.
• Duplex digital PCR demonstrated excellent repeatability, quantitative linear relationship, and relative LOQs, meeting quantification needs.

Conclusions:

• Digital PCR provides absolute quantification of specific genes, making it suitable for determining transgenic component content.
• The developed duplex digital PCR method is effective and satisfactory for quantifying transgenic soybean event DAS-68416-4.
• The gene copy ratio serves as a universal standard for expressing transgenic component content internationally.