DETECTING THE POSSIBLE ADULTERATION OF NON-GMO CORN AND SOY WITH GMO PRODUCTS

In recent years, non-genetically modified or organic products derived from common grains have been adulterated or contaminated with similar but cheaper genetically modified (GMO) or lower quality grains. Corn and soy are two of the most common GMOs grown in the United States. At the time this report was written, organic corn was worth $7.79 per bushel and GMO corn was worth $3.44 per bushel. Organic soy sells for about $20 per bushel whereas its GMO version sells for about half as much. This study investigated what percent by weight of GMO corn chips can be added to organic corn chips without being detected by Polymerase Chain Reaction (PCR) and gel electrophoresis. The same investigative approach was used for organic tofu and GMO soy ice cream. All foods were purchased at a supermarket and fine pastes were prepared out of organic and GMO corn chips as well as organic tofu and GMO soy ice cream. The amounts of GMO corn chips in the corn chip paste ranged from 1% to 50%. The same ratios were used in preparing test samples of GMO soy ice cream in the organic tofu. DNA from the pastes was amplified using PCR. Samples of amplified DNA were analyzed for the presence of a GMO sequence, the cauliflower mosaic virus 35S promoter CaMV35S, using gel electrophoresis. For pastes derived from corn chips, percentages of 6% GMO and below were undetectable by this method, and percentages of 7% GMO corn chips and above were detectable. Regarding soy foods, the PCR test did not detect 3% GMO tofu and below, while it did detect 4% GMO tofu and above. During the testing for GMO soy, experimental difficulties arose that compromised the conclusiveness of the findings. This research suggests that it is possible to use PCR and gel electrophoresis to reveal GMO food adulterants in ratios of 7% or more by weight.