Investigation of Genetic Modification in Maize, Papaya,

Fritos® Corn Chips, and Natura® Soymilk

Frank Soto5/6/2011

Background

Genes to identify: 35S promoter, NOS terminator, and PSII

Methodologya) DNA Extractionb) DNA Amplificationc) Electrophoresis of DNA

Analysis of Results

Conclusion

Index

GMO’s are organisms that have been modified through genetic engineering.

In the United States, under guidelines issued by USDA's Animal and Plant Health Inspection Service, genetic engineering is defined as the genetic modification of organisms by recombinant DNA techniques (USDA, 2007)

According to the USDA, crops have been genetically modified ever since 1996.

These crops have all kind of modifications, such as: herbicide tolerance, pesticide tolerance, and bacterial resistance.

GMO Background

Genes Structure of a gene

Steps for genetic modification of a crop:

a) First, find the ideal protein to express.

b) Isolation of the gene of interest.

c) Insertion of the ideal promoter and terminator

d) Back cross to highest-yielding plants

35S promoter from the cauliflower mosaic virus (CaMV 35S)

Nopaline synthase (NOS) terminator from Agrobacterium Tumefaciens

Photosystem II (PSII)

Genes to Identify

Our hypothesis is that the genes 35S and NOS will appear in the gel. The 35S gene will be found at 203bp and NOS at 225bp. We believe the corn will be identified as GMO while the soymilk won’t. In addition, both the corn chips and the papaya will be indentified as GMO.

Hypothesis

Methodology

DNA Extraction

a) Weighing and Grinding of samples

b) Pipette 50µL of Slurry into tube containing Instagene matrix.

c) Flick tube and place in a 95 degrees celsius water bath for 5 min.

d) Place tubes in microcentrifuge for 5 min.

Non-GMO

Test food

Test food

50µL of sample slurry

500µL of Instagene matrix

50µL of sample slurry

500µL of Instagene matrix

50µL of sample slurry

500µL of Instagene matrix

PCR

a) 20µL of indicated master mix is dispensed to each of the samples.

b) 20µL of DNA samples are dispensed to their corresponding tubers.

c) Once the samples have been dispensed, the tubes are put in the thermal cycler.

Non-GMO PMM

Non-GMO GMM

GMO (+) PMM

GMO (+) GMM

Test PMM

Test GMM

Test PMM

Test GMM

PMM= Plant molecular markerGMM= Genetic molecular marker.

Electrophoresis

a) The gel used was a 3% Agarose gel.

b) To prepare for electrophoresis, 10µL of Orange Loading dye was deposited into each of the samples.

c) 20µL of Molecular weight ruler(mwr) was deposited to wells to wells 1 and 10.

d) 20µL of samples were dispensed to wells 2-9.

e) Electrophoresis was run for 30min. at 100V.

f) After electrophoresis, the gel was stained with ethidium bromide pads for 20min.

1 Molecular weight Ruler

2 Non-GMO PMM

3 Non-GMO GMM

4 GMO (+) PMM

5 GMO (+) GMM

6 Test PMM

7 Test GMM

8 Test PMM

9 Test GMM

10 Molecular Weight Ruler

Analysis of Results

Frank’s Gel

Lester’s Gel

One can conclude that the maize was genetically modified, while the soymilk, papaya, and corn chips are inconclusive.

The experiment must be repeated because the results were affected by human errors, such as bad pipetting technique.

Conclusion