For South African food and feed businesses, choosing the right test — whether screening, quantification, or event identification — determines whether your results are meaningful, compliant, and fit for purpose.
Why GMO testing varies (Screening vs Quantification vs Event ID)
GMO testing is not a one-size-fits-all process. Different tests serve different purposes:
- Screening tests: These detect the possible presence of GMOs by targeting common genetic elements like the p35S promoter and tNOS terminator.
- Quantification tests: These measure the percentage of GMO content in a sample, often required for labelling.
- Event-specific tests: These identify and quantify specific genetically modified events, crucial for regulatory compliance and export.
How PCR detects GMOs (p35S, tNOS, qPCR)
Polymerase Chain Reaction (PCR) is the cornerstone of GMO testing. It amplifies DNA to detect genetic modifications. Key methods include:
- Screening PCR: Targets common genetic markers such as p35S and tNOS.
- Quantitative PCR (qPCR): Measures the GMO percentage in a sample.
- Event-Specific PCR: Identifies specific GM events and can also quantify them.
Step-by-step GMO testing workflow
- Sample collection: Food, feed, or seed samples are collected for analysis.
- Screening: Initial tests detect the presence of GMOs.
- Follow-up testing: Positive screening results lead to quantification or event-specific identification.
- Reporting: Results are compiled to meet regulatory or customer requirements.
Right test for labelling
Selecting the appropriate test depends on your specific needs:
- Labelling compliance: Quantification tests ensure GMO content is within legal limits.
- Customer specifications: Event-specific tests verify the absence or presence of particular GMOs.
- Export requirements: Tailored testing strategies meet international standards.
GreenHill labs testing services and support
GreenHill Labs offers comprehensive GMO testing services in South Africa, including:
- Screening tests: Detect common genetic elements.
- Quantification tests: Measure GMO content accurately.
- Event-Specific tests: Identify and quantify specific GM events.
Our team provides tailored testing strategies and technical support to ensure your products meet all regulatory and customer requirements.
