GMO Detection Lab Report: The Main Objectives

Gmo Detectionlab Report 3objectivethe Main Objectiv

The main objective of the GMO detection experiment is to extract DNA from food material and to test for genetic modification in processed food products. The background emphasizes that genetically modified (GM) foods are increasingly common, with over 60% of food products in the United States being genetically modified. Genetic modification involves altering the DNA of food in ways that are not naturally occurring, typically through genetic engineering techniques that introduce or modify traits. Since the first commercial GM crop in 1994—a genetically modified tomato (Flavr Savr)—the focus has primarily been on high-demand crops resistant to herbi- and pathogens, such as soybeans, papaya, canola, corn, and cotton. As the production and consumption of GM foods rise, the need for reliable testing methods has also increased to satisfy consumer demand for both GMO and non-GMO products.

Two main techniques are employed for GMO testing: protein-based lateral flow strip tests or ELISA, which detect specific proteins produced by GM organisms, and DNA-based methods like Polymerase Chain Reaction (PCR), which analyze the genetic material directly. PCR is particularly useful because it can identify the presence of specific genetic sequences associated with GM technology. This laboratory experiment, therefore, focused on extracting DNA from food samples and performing PCR testing to identify the presence of GMOs.

Procedure

The experimental procedure began with the preparation of equipment and materials, including washing and drying mortars and pestles, and labeling two screw cap tubes with 500 µL InstaGene matrix, one designated for “non-GMO” and the other for “test.” A known non-GMO food sample and a test food sample (Cheetos chips) were weighed (1 gram each) and placed in separate mortars. To each sample, five milliliters of distilled water were added, and the mixture was ground for approximately two minutes until a slurry formation was achieved. The slurry was further diluted with an additional five milliliters of distilled water, ensuring a smooth consistency suitable for Pipetting.

From each slurry, 50 µL was transferred into the respective InstaGene matrix-containing tubes using a pipette, which were then recapped and shaken thoroughly to mix. The mortar was washed with detergent and dried before repeating the process for the other sample. The tubes were then centrifuged at maximum speed for five minutes and kept on ice for subsequent DNA analysis.

PCR Setup and Analysis

Six PCR tubes, each with 20 µL capacity, were prepared with specific combinations of DNA samples, primers, and master mixes. The first tube contained 20 µL of non-GMO control DNA combined with plant master mix. The second tube contained non-GMO control DNA with GMO master mix. The third tube contained the test food DNA mixed with plant master mix, and the fourth with GMO master mix. The fifth and sixth tubes served as positive controls with GMO DNA, using plant master mix and GMO master mix respectively. The remaining tubes included molecular controls and an empty control. All tubes were stored at -20°C until PCR amplification.

The PCR thermal cycling protocol was followed according to the specific primer and reagent instructions. After amplification, the PCR products were analyzed via gel electrophoresis. The gel revealed bands indicating the presence or absence of GMO-related DNA sequences. A 200 bp band observed in lane 5 confirmed that the test food (Cheetos chips) contained GMO genetic material, indicating a positive GMO test result.

Results and Interpretation

The gel electrophoresis results demonstrated that the test food (Cheetos) tested positive for GMOs, evidenced by the presence of a 200 bp band in lane 5. This band indicates the presence of GMO-specific DNA sequences, confirming the food's genetically modified status. The positive control lanes (lanes 5 and 6) also showed bands at the expected size, validating the accuracy of the PCR process.

In contrast, the non-GMO controls (lanes 1 and 3) showed no such bands when tested with GMO primers, confirming that these samples did not contain GMO DNA. The absence of bands in lane 2, which contained non-GMO food and GMO primers, reinforced that non-GMO foods do not contain GMO-specific sequences, thus providing a negative control to ensure specificity. The presence of bands in control lanes and their absence in others underscores the reliability of the PCR technique for GMO detection.

Conclusion

The primary conclusion drawn from this experiment is that the tested Cheetos chips are genetically modified, as evidenced by the presence of the 200 bp band in the PCR gel. The results suggest that the food product contains GMO DNA, consistent with the genetic modifications commonly used in food crops of similar nature. The controls validated the procedure's specificity and accuracy, illustrating the effectiveness of PCR as a tool for GMO detection in processed foods.

Understanding the presence of GMOs is crucial for regulatory, health, and consumer preference reasons. Reliable detection methods like PCR enable authorities and consumers to identify GMO contents accurately, facilitating informed choices and adherence to labeling regulations.

References

• Huang, H., Cheng, F., Wang, R., Zhang, D., & Yang, L. (2013). Evaluation of four endogenous reference genes and their real-time PCR assays for common wheat quantification in GMOs detection. PLOS One, 8(9).
• Brookes, G., & Barfoot, P. (2020). The economic and environmental impacts of genetically modified crops: A case study of soybean and maize in the United States. GM Crops & Food, 11(1), 99-119.
• James, C. (2018). Global Status of Commercialized Biotech/GM Crops: 2018. ISAAA Report No. 53. International Service for the Acquisition of Agri-biotech Applications.
• Qaim, M. (2016). The economics of genetically modified crops. Annual Review of Resource Economics, 8, 37-56.
• Lucht, J. M. (2015). Public acceptance of pesticides and GMOs: A review. Sustainability, 7(3), 1700-1722.
• Fernández-Cornejo, J., McBride, W. D., & Osteen, C. (2014). Genetically engineered crop varieties in the United States. U.S. Department of Agriculture, Economic Research Service.
• Kung, S. F. (2017). Detection and identification of genetically modified organisms (GMOs). Critical Reviews in Biotechnology, 37(4), 533-544.
• Sharma, S., & Singh, B. (2019). Molecular detection and analysis of genetically modified crops: An overview. Journal of Food Science and Technology, 56(4), 1857-1867.
• Mezzalama, M., et al. (2019). Advances in GMO detection techniques. International Journal of Molecular Sciences, 20(24), 6292.
• European Commission. (2020). GMO legislation. European Union Regulation EC No 1829/2003. https://ec.europa.eu/food/plant/genetically_modified_products/legislation_en