GMO's results

After learning all about genetically modified organisms over the past week from Mr.Chugh, we have finally finished our three day lab and have found results. Each lab table was able to bring in a fruit or vegetable to test to see if it was genetically modified. On the first day we extracted the DNA from our food samples (our control and test foods). We measured out about one gram of each substance and then added water into a mortar where we used a pestle to form a "slurry". Once we had ground the substance smooth enough we pipetted it into a test tube. We then added our test tubes to a water bath at 99 degrees Celsius for five minutes, followed by centrifuging for five minutes. That completed our first day of extracting genetic material from our test food.

On the second day, we returned and added "master mix" to each sample. After adding it to each PCR tube we put it in the thermal cycler. The cycler goes through three cycles. The first is at about 95 degrees Celsius, this is where denaturization occurs (DNA is unravelled), the second temperature change is to about 60 degrees Celsius where the primer binds, and the last stage is about 72 degrees where DNA polymerase appears.

On the third day of this lab, where we did gel electrophoresis. After retrieving our PCR tubes, we added loading dye to each sample and mixed them. Next, we added 20 micro liters of each sample into the gel. After loading them in we ran an agarose gel for 3 minutes on 200 V.

When we returned on the fourth day, we found our results! Our food (broccoli) was organic, meaning it was not genetically modified! After evaluating our electrophoresis we found bands in the second, fourth and sixth lanes. These were the lanes that had GMO primers added to them, meaning they would show up in our testing, unlike the plant primers because the plant primers were looking for non-modified genes to code for. The GMO primers were looking for modified genes because it can only  copy them if it recognizes the genes.

Possible causes for error: Our results could have been more accurate had the experiment been done in a sterilized lab with better pipetting and more precise timing with water baths.
 http://www.youtube.com/watch?v=dvlpCxjxC1g    (picture is a little blurry)

Taking over the World

Genetically modified organisms are taking over stores worldwide. They are foods that have been "hand selected" where the genes that are desired are placed directly into crop plants. This allows certain crops to gain traits that allow them to stay fresh longer, resist cold, grow bigger and taste better. The idea of genetically modified foods have created a very controversial front. Some argue that there  is a potential that we create "super-weeds" or that "super- bugs" will evolve that can resist pesticides. Some people are concerned that if genes are taken from other organisms then there is the risk that if one was allergic to a certain organism that they could have a reaction to the new GMO. But, on the other hand GMO's are creating a whole new market for farmers and people in the business. Before genetically modified plants were discovered being a farmer was a risky business. Some years you could have an abundant crop and others you produced and sold next to nothing. The idea of crops that cut costs on pesticides or could almost guarantee being bigger and stronger was very intriguing and promising for the business.

At this time in the United States GMOs do not need to be labeled. So when people go out to buy fruits or vegetables they have no idea whether what they are eating is genetically modified. For the common person this is a fact. But, for a amateur scientist, this is hardly a problem. There is a way to find out if your food is genetically modified! This is what we will be doing in our lab.

First, in order to genetically modify a plant you must take the plasmid of a specific plant. Then you find the gene of interest, such as a TI plasmid (tumor inducing) which will go into agro-bacteria and then into a new plant cell. In order for us to find out if our food is genetically modified we must grind/break up the cell wall and nuclear membrane of the plant cell. Next we will put the sample into a hot water bath (at 99 degrees celsius). We will be adding DNAse, which destroys DNA if we open the cell membrane. The second day of our study we will compare plant DNA with DNA of a genetically modified organism. On the third day of our lab we will use gel electrophoresis to see which genes are present between our control and our samples. As a control we are using an organic, non-genetically modified organism. Our goal is to find out if food we have around the kitchen is genetically modified without us even knowing.

http://www.youtube.com/watch?v=xfeTtsaZ0pQ