Genetically modified organisms, or GMOs, are living plants or animals whose DNA has been altered through genetic engineering.
In most cases, a GMO has its genetic code changed by splicing in a gene from a different plant or animal -- these animals or plants are often referred to as "transgenic" organisms.
As a well-known example of a transgenic species, first consider a spider web, made of spider silk.
GMO researchers took a gene for making silk from a spider and spliced it into the DNA of a goat.
The goats then produce a protein for making spider silk in their goat milk. Medical researchers harvest the silk protein and create super-strong, lightweight spider silk, which has a number of medical and industrial uses.
But Who Needs a GMO?
In some ways, genetically modified organisms are simply carrying on the work that plant and animal breeders have been doing for centuries, i.e., enhancing traits like a racehorse's speed or a cow's milk production, while also eliminating bad traits like susceptibility to disease.
Traditional breeding, however, is a slow process that's fraught with error. In addition to being relatively fast and easy to develop, no breeder can create transgenic GMO species like the aforementioned fish tomato.
By far the greatest application of GMOs has been in agriculture, to create genetically modified foods.
Plants are genetically modified for disease resistance, for drought tolerance, for resistance to hot or cold temperatures, for added nutrition, and for resistance to insect pests. By genetically introducing pest resistance, scientists hope to reduce the use of chemical pesticides.
GMOs have also developed for pharmaceutical uses, and for "phytoremediation," the use of plants to clean up toxins and other hazardous materials from contaminated soil and water.
Some trees, for example, have been genetically engineered to pull dangerous heavy metals out of contaminated soil.
But other GMOs are not as environmentally friendly: Herbicide resistance can also be genetically induced, and crops plants that have a tolerance to herbicides can survive even when nearby plants -- specifically, weeds -- are sprayed with a deadly herbicide.
Monsanto Company, for example, has developed a soybean plant that's resistant to Monsanto's popular herbicide Roundup. This example of factory farming lets farmers spray their soybean fields with Roundup, kill all the weeds and other plants, and leave only the soybean plants.
How Safe are GMOs?
The issue of safety has swirled around GMOs since genetic researchers first introduced them in the 1970s. While proponents have heralded the almost-limitless potential of GMOs to fight disease, improve crop yields and safeguard the environment, critics have decried the development of genetically tweaked "Frankenfoods" that could spread from agricultural fields into the rest of the environment, with potentially catastrophic ecological results.
Among the critics' most serious charges are GMOs' potential to stimulate the rise of antibiotic-resistant "superbugs" and pesticide-resistant "superweeds" that require the use of increasingly powerful drugs and hazardous chemicals.
There's also some evidence that GMOs are largely used to increase profits for agribusiness interests at the expense of smaller farmers who do not use GMO crops.
GMO Use and Regulation Worldwide
Because of the safety concerns associated with GMOs, the European Union has instituted the world's strictest measures to limit the use of GMOs throughout Europe, and only a few GMO crops are raised there. Europe also has strict labeling requirements, and all GMO products available there must be labeled as containing genetically modified contents.
Other countries like Canada, China and Australia have some regulations in place regarding the use and labeling of GMOs. Other countries are developing regulations as GMOs become more widely used.
But in the United States, where the vast majority of GMOs are developed and grown, regulations regarding the development, use and labeling of GMOs are lax at best.
According to a series of reports in The New York Times, both the FDA and the USDA -- under heavy pressure from agribusiness -- "will not require any of these products, or foods containing them, to be labeled as genetically engineered, because they don’t want to 'suggest or imply' that these foods are 'different.'"
The political and scientific controversy over genetically modified organisms isn't likely to end anytime soon, and advocates for consumer rights and environmental health will continue to do battle with GMO industry giants like Monsanto, Archer Daniels Midland, Coca-Cola, DuPont, General Mills and other companies with huge financial ties to agribusiness and pharmaceutical research.