Genetically Modified Organisms (GMOs) are living organisms whose DNA has been altered by genetic engineering. Foreign genes have been inserted into the genome of these organisms. GMOs have widespread applications, such as biological and medical research, production of pharmaceutical drugs, experimental medicine, and (yep) food. Today the broadest, and most controversial, use of GMOs is crops.
How it started…
By the 1970s, Round Up had become the most widely used herbicide (weed killer), but Round Up worked a little too well – it killed the crops as well as the weeds. So Monsanto, the corporation that created Round Up, used genetic engineering to create a new breed of corn which was “Round Up Ready” – it could live when sprayed with Round Up herbicide. Pretty cool, except that now the farmers have to buy their seeds from one company (not to mention the disturbing fact that a few decades ago farmers only sprayed when it was absolutely necessary, but now we’re developing crops designed to be sprayed). GMOs grew from here. In 1994, GMOs expanded beyond cattle feed and hit our supermarkets in the form of FlavrSavr tomatoes.
Since the 90′s, the growth in the amount of GMOs has been remarkable. Today there are all kinds of GMOs, such as tomatos that have a flounder gene to make them better withstand cold weather, and corn in which the corn itself is a registered pesticide because bugs that eat any part of it die. The United States Department of Agriculture (USDA) reports that in the US, depending on the year, 81-86 percent of all corn planted, 88-90 percent of all soybeans planted, and 81-93 percent of all cotton planted are genetically modified.
How it works…
So, you want to put a flounder gene into a tomato so that it can withstand cold weather, but HOW do you get that flounder gene into the tomato? You must invade the tomato cells with the flounder gene. And what’s good at invading cells? Viruses and bacteria.
After 12 years of searching, Monsanto found a bacteria in soil that was naturally immune to Round Up herbicide. Their goal was to genetically engineer DNA from these bacteria into various plants. This next part gets a bit scientific, so bear with me.
They cut out the sequence of DNA that is resistant to Round Up, but simply inserting this sequence alone into a corn plant has no effect because cells will naturally reject foreign DNA. So, they use E. coli bacteria to ferry the DNA to the plant cell’s nucleus. First, gaps are created in the E. coli bacteria DNA. This broken E. coli DNA is mixed with the Round Up resistent bacteria DNA and the two broken strands of DNA join. The new hybrid DNA is then able to penetrate the corn cells because of it’s E. coli bacterial invasion properties (that’s not a scientific term). This capacity of bacteria & viruses to invade cells is what has alot of people edgy about biotechnology.
(Just to be thorough, I’ll mention that there are also 2 other methods of injecting foreign DNA into cells, both involve piercing tiny holes in the cell walls, but I won’t bore you with the details of those techniques.)
Then, there is one final step. An “antibiotic marker” gene is inserted into the cell. This is a gene which is naturally resistant to a specific antibiotic, which they somehow use to make sure the desired genetic trait is being expressed. This is another controversial issue of GMOs because one of the most cataclysmic forces in the food system right now is the fact that the medical community is worried about the loss of antibiotics. No one is really sure yet how using these antibiotic marker genes in GMOs might contribute to the problem, but it is a large focus area of the biomedical community.
“As we move forward with this genetic manipulation, we’ll start seeing pieces of DNA reacting with each other in ways that are totally unpredictable. This is probably the largest biological experiment humanity has ever entered into.” -Dr. Ignacio Chapela, Microbial Ecologist, University of California Berkeley
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Breakfast: An apple
Lunch: A (vegan) twice-baked potato and leftover black-eyed-peas
Dinner: Vegetable ravioli
