Genetically Modified Organisms (GMO) have had specific changes introduced into their DNA through genetic engineering. This is not the same thing as selective breeding, where organisms have been modified over time from their wild ancestors. Genetic engineering involves isolating a specific gene in one plant or animal and inserting that gene into a separate type of plant or animal. The new gene becomes a part of the DNA and is regulated in the same way as other genes. Genes may be inserted to keep the plant resistant to certain pests, pesticides, herbicides, and viruses, to increase the amount of vitamins or nutrients, and to lengthen the shelf life.
GM foods were first put on the market in the early 1990's and typically include soybean, corn, canola, cotton, potatoes, peanuts, tomatoes, tobacco, sweet peppers, and lettuce, among others. Currently the US and Canada do not require labeling of GM foods.
A few controversial issues with GMOs:
1. Patents on Seeds. Typically, farmers save their own seed from year to year. What's the point in buying more seed when there's an abundance leftover from the garden? However, if farmers followed this practice with genetically modified seeds, the seed developers would not really make a profit from their breeding work. Patents, contracts, etc. are in place to prevent farmers from saving seeds of GM plants. The seed developers are encouraging reliance on their own brand of plants, which could easily creat monopolies over the farmers.
2. What's next for GM foods? How much will our food be changed because of genetically modified engineering and how will these changes effect our bodies and environment? Animals may be engineered to grow larger or more quickly, fruit trees may produce years earlier, and typical allergens may be removed from wheat, nuts, etc. The possibilities are endless, and the risks are largely unknown.
3. Cross-contamination with Allergens. A study in the 1990's injected a soybean with a protein from a Brazil nut. Test results showed people allergic to Brazil nuts were also allergic to the GM soybean. Almost any food can be an allergen or intolerance to someone: wheat, strawberries, eggs, nuts, soy, corn, etc. Unless foods are clearly labeled with where the modified genes come from, those with allergies/intolerances will not know for sure if the food will effect them.
4. There can be good results. Selective breeding takes years and years to accomplish, and you can only cross-breed plants with plants. Genetic engineering allows scientists to quickly take a gene from an insect, bacteria, animal, etc. to be placed in a plant (or other insect, animal, etc.). Supporters argue that GM foods improve nutrition (Golden rice boosted with Vitamin A), will require less insecticide use because plants will have their own insect-repelling qualities, and can help with world hunger by being more drought-, salt-, or cold-resistant. (A gene from cold water fish has been implemented into tobacco and potato plants so that they can better tolerate cold temperatures that normally kill conventional plants.) Also, allergens may be removed, such as in the hay fever-free grass. Pharmaceuticals are working on edible drugs and vaccines (think Hepatitis B in a tomato) that will be easier to ship, store, and administer to 3rd world countries.
5. There can be destructive results. GM insect-repelling plants may speed up the evolution of insecticide-restistant pests. New allergens may develop, since we're not used to consuming so much of whatever will be injected (like insects or specific bacteria). The GM crops will become superweeds that are more resistant to herbicides. Gene transfer is also a serious threat between GM and conventionally grown crops. This would be particularly harmful if pharmaceutical crops crossed with food crops. These crops don't have to be grown side by side to be cross-contaminated. The wind or bees may carry the pollen elsewhere, birds may carry seeds away, "leftovers" may be in the soil when previous GM crops are tilled under at the end of the season. This is not a future threat...it's present today. In 2001, genetically modified genes had spread from US corn crops to Mexico - into their native varieties grown on small farms. There can also be unintended harm to other organisms. One study showed pollen from GM corn caused high mortality rates in monarch butterfly caterpillars.
What do you do now?
Good question. It's up to you to decide if you're for or against GMOs. Personally, I'm against it. I feel like there are too many in it for the money rather than the advantages over hunger, and that there are too many risks (known and unknown).
If you're looking to buy non-genetically modified foods, here's a great list of common processed foods that shows which are GM and which aren't: True Food Now.
To know if your produce is genetically modified, look at the little sticker with the numbers. For conventionally grown produce (grown with pesticides, herbicides, and other chemicals), the code on the sticker consists of four numbers. Organically grown produce has five numbers, the first of which will be a 9. Genetically engineered (GM) produce has five numbers, the first of which will be an 8.
Check out the Genetic Engineering Action Network for more tools against genetic modification.
Sources: Wikipedia, New Scientist, ProQuest, and GEAN
