Testing GMO Content of Food Products

In order to double food production for the increasing population of the world. That is predicted to be around 11 billion people by the year 2050 (James and Krattiger, 1996). The scientists and the developing communities believed that the conventional agriculture process would not produce enough food and resources to sustain the increasing population. This has lead scientists to research new technologies that will help increase the yield of crops. These new technologies are known as biotechnology or commonly known as genetically modified organism (GMO) (James and Krattiger, 1996). This technology involves the application of genetic engineering in biotechnology which involves the use of transgenic crops this is when a gene or a genetic contrast has been introduced into an organism by molecular techniques.

The use of genetically modified crops have been a controversial issue since 1971 this was during the time the first genetically modified organism was being developed (James and Krattiger, 1996). The controversial issues were due the concerns about the biosafety of the genetically modified organisms. These concerns of the genetically modified organisms have resulted in government regulations being put in place to monitor the production of the genetically modified organisms (James and Krattiger, 1996). The genetically modified organism must undergo trails to assess the potential risks of the organism before they are available to be commercially grown and sold (James and Krattiger, 1996). The government division that recognize the risks involved in genetically modified organisms is known as the office of gene technology regulator (OGTR). This corporation supervises all of the research and production of genetically modified organism (Huggett, 2014).The risk that are assed is the possibility that the introduced genes in the genetically modified organisms can spread and be introduced into neighboring crops and plant species. Some of the problems that can be caused by genetically modified organism can arise from modifying organisms to be herbicide resistant (Peterson, Cunningham et al., 2000). If this gene spreads into non target species It could highly damage the agricultural industry (James and Krattiger, 1996). This modification can also reduce the paddock biodiversity because of the extra amounts of herbicide being used on herbicide resistant crops. This would reduce the ecological services that are provided by agricultural systems (Peterson, Cunningham et al., 2000). Another risk that can be caused by genetic modification is the virus resistant gene. This GMO can cause the virus to move to non-target species where the viruses fitness will increase this could result in endangering other species of plants.

Other concerns about the use of genetically modified organisms is the potential effects they may have on human health. Food allergies are a common risk in genetically modified organisms. If the novel protein in GM foods come from a known source that causes allergies in humans. Such as proteins being introduced from plants that aren’t normally consumed by humans there is a concern that the protein could cause people to develop a provoke immune response that will cause allergies in humans to increase. Other examples of concerns for human health is the chance of toxicity in GM foods to increase. Genetically modified foods can also decreases the nutrition values of food.

The OGTR use technology to detect the genetically modified organisms in foods. One of these technologies is known as PCR polymerase chain reaction. Using this technology it is possible to detect the exact sequence that has been inserted in the PCR machine can detect the GMO.

Method

The method that was used in this experiment followed the lab manual exactly.

Huggett, D. M. (2014). SCB2222: Cellular and Meclular Biology unit materials and lab manual. Joondalup, Edith Cowan University. 1.

Results

From looking at the results that have been recovered from the PCR tests in Table 1 the results showed that there was only one genetically modified organism out of all the foods that where tested. The only foods that showed a positive result for the GMO primer was the positive control group. The GMO control group also showed a positive result for the plant primer for the photosystem 2 gene. Another food that tested positive for the GMO was the papaya. The rest of beside 4 tested negative for the GMO but positive for PMM. These where the Kiwi Fruit, Celery, Soy Sauce, Corn Wrap, Polenta, Corn Chips, Apple and a tortilla. Only one produce tested negative for both GMO and PMM this was the Banana. There were four errors in total for the experiment that resulted in no reading at all these were the Corn Flour, Soy cheese, Bread Mix and Carrot.

Discussion

During this experiment with the types of methods we have used we were able to test for genetically modified organisms in the selected food products that were chosen. From the experiment on the different foods using the PCR we were able to see that the majority of the food tested are in fact not GMO. Beside the four errors that occurred during the PCR process the experiment was successful in identifying genetically modified organisms. The errors that did occur was due to human fault from either not preparing the sample properly. The errors may also have occurred from accidently spilling the food sample outside of the wells in the gel of the PCR machine which lead to bad readings. The only things that tested positive to being a genetically modified organism is the positive GMO control and the one food sample that tested positive for the GMO was the papaya. The only sample that tested negative for the PMM was the Banana this means I it didn’t test positive to contain the Photosystem 2 gene.

As mentioned before in the introduction of the experiment the method that is widely used to identify genetically modified foods is the polymerase chain reaction PCR (Harvey Lodish, 2013). This method depends on its ability to alternate and denature the double strand of DNA molecules. The PCR method begins by heating up the DNA to 95 â-¦C this denatures the DNA into single strands it is then recombined into specific regions through the use of specific loci and primers (Harvey Lodish, 2013). The DNA molecules are reformed by the use of heat resistant enzymes. Once this process is completed the DNA fragments are then put through an electrophoresis treatment this treatment involves an electrical current to pass through the 3 percent agarose gel matrix which encourages the DNA molecules to move and separate to different locations this is determined by their molecular weight (Harvey Lodish, 2013). The locations then form markings in the gel which is then used to determine whether the desired sample has been genetically modified or not.

PCR technology’s high level of sensitivity for detecting GMOs explains why it is the method of choice for scientists (Holst-Jensen, Rønning et al., 2003). While using PCR method of detection the most important factor to remember is the choice of sequence motif. The sequence motif is important to help decide what target gene that you require to detect in the PCR sequencing (Holst-Jensen, Rønning et al., 2003).

Foods in Australia have to be labeled with what their contents is and what ingredients is used in the products. Genetically modified foods have to be labeled if they contain novel DNA, proteins these products must be labeled that they are genetically modified (Zealan, 2013). The labeling of genetically modified foods in Australia is not a about the safety of the product. These labels are just there to help the consumer make a choice. The reason that this is not about the safety of the product is because all of the genetically modified organisms are monitored by OGTR (Zealan, 2013). This corporation makes sure that the biosafety won’t be affected by GMOs. Some GM foods are exempt of being labeled in such a mater because they do not contain any novel DNA or proteins or the characteristics of the organism hasn’t been changed (Zealan, 2013).

References

Harvey Lodish, A. B., Chris A. Kaiser, Monty Krieger, Anthony Bretscher, Hidde Ploegh, Angelika Amon (2013). Molecular Cell Biology 41 Madison avenue, New York NY 10010, W.H. Freeman and Company.

Holst-Jensen, A., et al. (2003). “PCR technology for screening and quantification of genetically modified organisms (GMOs).” Analytical and Bioanalytical Chemistry 375 (8): 985-993.

Huggett, D. M. (2014). SCB2222: Cellular and Meclular Biology unit materials and lab manual. Joondalup, Edith Cowan University. 1.

James, C. and A. F. Krattiger (1996). “Global review of the field testing and commercialization of transgenic plants: 1986 to 1995.” ISAAA Briefs (1).

Peterson, G., et al. (2000). “The risks and benefits of genetically modified crops: a multidisciplinary perspective.” Conservation Ecology 4 (1): 13.

Zealan, F. S. A. N. (2013). “GM food labelling.” Retrieved 13 may 2014, from http://www.foodstandards.gov.au/consumer/gmfood/labelling/Pages/default.aspx.

Appendices

Methods and materials

DNA extraction

1. Collect two screw cap tubes and add 500μL of well-mixed InstaGene matrix and label one non-GMO and one test.
2. Weigh out 0.5–2 g of the certified non-GMO food control and place in mortar.
3. Add 5 mL of distilled water for every gram of food.
4. Grind with pestle for at least 2 min until a slurry is formed.
5. Add 5 volumes of water to every gram of food and mix or grind further with pestle until you believe the slurry is smooth enough to pipette.
6. Transfer 50μL of ground slurry to the screw cap tube containing 500μL of InstaGene matrix labelled non-GMO.
7. Recap tube and shake well.
8. Wash mortar with detergent and dry.
9. Repeat steps 2-8 using test foods.
10. Place tubes in 95 â-¦C water bath for 5 minutes.
11. Centrifuge for 5 minutes at maximum speed. 12. Store at 4 â-¦C until next lab
12. Store at â-¦C until next lab
13. Finally, make sure that your samples are recorded onto Blackboard during the lab, include the way the tubes were labelled
14. Make sure that at least one non-GMO control sample is processed in the class.

Set up for PCR

1. Place non-GMO and test sample tubes in 95-100â-¦C water bath for 5 min.
2. Place tubes in centrifuge in a balanced conformation and spin for 5 min at maximum speed. This pellets out the InstaGene Beads.
3. Label PCR tubes with a number and your initials:

Each sample requires two PCR tubes: one for the Plant master mix and another for the GMO master mix

4. Record which PCR reaction and test material correspond to which tube label on the lab computer
5. Make up the PCR mixtures by adding 10µL of master mix FIRST, then 10µL of sample DNA. Take care not to transfer any of the InstaGene beads to your PCR reaction. If the beads are disrupted, recentrifuge your DNA samples to pellet the beads. Use a fresh tip each time. Mix using your pipette.
6. Recap tubes
7. Pulse spin in the centrifuge to ensure all the solution is at the bottom
8. Place the PCR tubes in the thermal cycler when ready.

Preparation of agarose gels

1. Prepare a 1.5% agarose gel mixture by placing 1.5g of agarose in 100ml of 1xTAE buffer. Heat agarose in microwave oven until it has melted. This is enough for several gels.
2. Prepare an agarose gel mold.
3. Place a wall comb towards one end of each gel mold, ensuring that the teeth are just off the mold.
4. Once the agarose has melted, add SybrSafe (1µl to 60ml of agarose), gently mix and carefully pour agarose into gel mold to a thickness of 3-4mm.
5. Once the gel has set, remove the comb and casting mold, taking care to prevent the gel from sliding off.

Loading and running gels

1. Set up your gel electrophoresis apparatus as instructed using 0.25xTAE running buffer to cover the gel.
2. Thaw samples.
3. Place PCR tubes in 95-100â-¦C water in bath for 5 min.
4. Mix each tube well and then place tubes in a centrifuge in balanced conformation and spin for 5 min at maximum speed.
5. Using a fresh tip each time, add 5µl of orange G loading dye to each sample and mix well.
6. Mix 20µl PCR molecular mass ruler with 5µl of orange G loading dye.
7. Prepare a diagram showing how the samples will be loaded onto the gel. Note the positive and negative electrodes on the gel and make sure one of the center lanes is loaded with PCR molecular mass ruler.
8. Load 20µl of the PCR molecular mass ruler and each sample onto your gel according to the diagram.
9. Run the agarose gel at 200 V for no longer than 20 minutes. Do not let the orange dye front migrate out of the agarose gel.
10. When electrophoresis is complete, turn off the power and remove the lid from the gel box.
11. Carefully remove the gel tray and the gel from the gel box. Be careful, the gel is very slippery. Nudge the gel off the tray with your thumb and carefully slide it into a plastic staining tray.
12. Record the gel using the GelDoc system using UV lights and post the image on blackboard with a document detailing what samples were loaded into which lanes. Make sure the gel is orientated the same way as the initial diagram and has not been turned over.

Scoring the results

1. Use the PCR molecular mass ruler to determine the size of each band on the gel.
2. Present the results in a table.
3. Use the molecular weights of the bands to identify the DNA bands as Per table.

Table 4.2 potential PCR products

Results

Lab 201 1030am gel

Lab 201 1330pm gel

Lab 202 1030am gel 1

Lab 202 1030am gel 2

Lab 202 1330pm gel 1

Lab 202 1330pm gel 2