Single and multi-laboratory validation of a droplet digital PCR method.

Area of Science:

• Food Science and Technology
• Analytical Chemistry
• Biotechnology

Background:

• EU regulations require validated analytical methods for authorizing genetically modified (GM) food and feed.
• Official laboratories need reliable methods for harmonized market control of GM products.
• Droplet digital PCR (dPCR) offers potential for sensitive and precise GMO quantification.

Purpose of the Study:

• To validate droplet digital PCR (dPCR) methods for genetically modified organism (GMO) analysis in food and feed.
• To assess if dPCR methods meet EU and international performance and acceptance criteria for GMO detection.
• To evaluate dPCR method performance in simplex and duplex formats for official GMO control.

Main Methods:

• Single-laboratory validation of dPCR methods against existing real-time PCR performance requirements.
• Multi-laboratory validation study assessing trueness and precision (repeatability, reproducibility) in simplex and duplex formats.
• Experimental assessment of DNA extraction influence, ingredient content, and result conversion for dPCR GMO analysis.

Main Results:

• dPCR methods demonstrated performance suitable for GMO analysis, meeting EU and international acceptance criteria.
• Relative repeatability and reproducibility standard deviations for duplex dPCR (MON810) were within acceptable ranges (1.8–16.5%).
• Relative bias was consistently below 25%, and DNA extraction had limited impact on measurement variability.

Conclusions:

• Validated dPCR methods are suitable for official GMO control in food and feed, ensuring reliable market surveillance.
• dPCR methods fulfill the stringent performance requirements set by EU and international guidelines for GMO analysis.
• The study supports the adoption of dPCR technology for robust and accurate GMO detection in regulatory settings.