When to use this test
A Real-Time PCR (RT-PCR) screen is used to determine the presence or absence of genetically modified traits expressed in transgenic corn and soybeans at very low levels of presence. A general screen for traits can be performed using 35S (promoter) and NOS (terminus) as amplification targets, or event-specific screens have been designed for a majority of commercially available traits.
ICIA is a NonGMO Project Approved Laboratory
What Technique is used
Bulk corn or soybean is ground in three replicates of 800 seeds each, and the DNA is extracted. The RT-PCR test screens the DNA using an Applied BiosystemsStepOne Plus®
RT machine and TaqMan®
MGB Probes (image at the right courtesy of the BiosystemsStepOne Plus brochure).
This procedure uses fluorescently-labeled probes and cycle-by-cycle data acquisition to generate an analyzed data set comparing the presence of a trait in a sample to a range of internal controls.
What do the Results mean?
Trait-specific standards of prepared percentage levels are compared to the test samples, which either fall above or below a 0.1% threshold. The presence/absence reported threshold can be varied to suit customer requirements.