A genetically modified organism (GMO) or genetically engineered organism (GEO) is an organism whose genetic material has been altered using genetic engineering techniques. These techniques, generally known as recombinant DNA technology, use DNA molecules from different sources, which are combined into one molecule to create a new set of genes.
Video and a lot more info after the jump…
This DNA is then transferred into an organism, giving it modified or novel genes. Transgenic organisms, a subset of GMOs, are organisms which have inserted DNA that originated in a different species. Some GMOs contain no DNA from other species and are therefore not transgenic but cisgenic.
Genetically modified (GM) foods are foods derived from genetically modified organisms. Genetically modified organisms have had specific changes introduced into their DNA by genetic engineering techniques. These techniques are much more precise than mutagenesis (mutation breeding) where an organism is exposed to radiation or chemicals to create a non-specific but stable change. Other techniques by which humans modify food organisms include selective breeding (plant breeding and animal breeding), and somaclonal variation.
GM foods were first put on the market in the early 1990s. Typically, genetically modified foods are transgenic plant products: soybean, corn, canola, and cotton seed oil. But animal products have also been developed. In 2006 a pig was controversially engineered to produce omega-3 fatty acids through the expression of a roundworm gene. Researchers have also developed a genetically-modified breed of pigs that are able to absorb plant phosphorus more efficiently, and as a consequence the phosphorus content of their manure is reduced by as much as 60%.
Critics have objected to GM foods on several grounds, including theoretical or imagined safety issues, ecological concerns, and economic concerns raised by the fact that these organisms are subject to intellectual property law.
Genetic modification involves the insertion or deletion of genes. In the process of cisgenesis, genes are artificially transferred between organisms that could be conventionally bred. In the process of transgenesis, genes from a different species are inserted, which is a form of horizontal gene transfer. In nature this can occur when exogenous DNA penetrates the cell membrane for any reason. To do this artificially may require attaching genes to a virus or just physically inserting the extra DNA into the nucleus of the intended host with a very small syringe, or with very small particles fired from a gene gun. However, other methods exploit natural forms of gene transfer, such as the ability of Agrobacterium to transfer genetic material to plants, and the ability of lentiviruses to transfer genes to animal cells.
The first commercially grown genetically modified whole food crop was a tomato (called FlavrSavr), which was modified to ripen without softening, by Calgene, later a subsidiary of Monsanto. Calgene took the initiative to obtain FDA approval for its release in 1994 without any special labeling, although legally no such approval was required. It was welcomed by consumers who purchased the fruit at a substantial premium over the price of regular tomatoes. However, production problems and competition from a conventionally bred, longer shelf-life variety prevented the product from becoming profitable. A variant of the Flavr Savr was used by Zeneca to produce tomato paste which was sold in Europe during the summer of 1996. The labeling and pricing were designed as a marketing experiment, which proved, at the time, that European consumers would accept genetically engineered foods. Currently, there are a number of food species in which a genetically modified version exists.
Safety is a major issue in this controversy. Adverse health effects need to be screened for, because health effects are dependent upon the modifications made. The need for screening and testing increases as more changes are made, and “second-generation” GMs will require more testing. To date no adverse health effects caused by products approved for sale have been documented, although two products failed initial safety testing and were discontinued, due to allergic reactions. Most feeding trials have observed no toxic effects and saw that GM foods were equivalent in nutrition to unmodified foods, although a few reports attribute physiological changes to GM food. However, some scientists and advocacy groups such as Greenpeace and World Wildlife Fund consider that the available data do not prove that GM food does not pose risks to health, and call for additional and more rigorous testing before marketing genetically engineered food.
Another area of controversy is what effect pest and herbicide-resistant crops have on ecosystems, by for example reducing the numbers of pest insects in farmland and impacting biodiversity, or by decreasing the use of insecticides. Attempts have been made to measure these effects by farm-scale trials of GM crops, although the interpretation of the results of these trials has been controversial. The risk and effects of horizontal gene transfer have also been cited as concerns, with the possibility that genes might spread from modified crops to wild relatives.
Are GMOs safe?
Research conducted at Southern Illinois University Carbondale supports the growing sentiment in the scientific community that genetically modified organisms – or GMOs as they’re commonly called – are safe for human consumption and for the environment.
No traces of a “foreign” gene wound up in the flesh or blood of 56 piglets fed genetically modified corn, SIUC researchers found.
While they did detect bits of the corn’s transgene in the stomach contents of 50 of the piglets, they found it in only one of the samples screened from the small intestine, suggesting further that the additional gene generally does not survive the digestive process.
This new study reinforced findings from earlier work with samples of contents from the small intestine and feces of larger pigs in which SIUC researchers found no remnants of the transgene at all.
“It seems like it degrades rapidly,” said swine expert Gary A. Apgar of the College of Agricultural Sciences.
“Most, if not all, of the transgenic material is gone by the time the digesta is excreted. We found no evidence that it is absorbed (into the animal), and the risk of its coming out in the environment in the form of waste is non-existent because we failed to find the gene in either the colon or the feces. While nothing can ever be guaranteed 100 percent safe, I think there’s no need for concern (about eating meat from animals fed transgenic diets).”
Apgar believes the weight of scientific evidence supports the idea that GMOs are safe.
“If we look at the amount of transgenic crops that have been created and the lack to date of negative effects in the human and animal worlds, I think that’s confirming what we have seen here (in this study),” he said.
The SIUC study, conducted with the help of Janet M. Beagle, now a doctoral student at Purdue University, is part of an overall look at GMOs as a component of swine diets. The Council for Food and Agricultural Research and the Illinois Corn Marketing Board paid for the research.
American farmers generally like GMOs, which provide improved yields, health, pest resistance and the like. Federal statistics show that in 2002, 34 percent of the country’s corn crop consisted of GMOs. Worldwide, more than 168 million acres are planted in biotech crops — a 4,000 percent increase over the last eight years, according to Truth about Trade & Technology, an Iowa-based biotechnology advocacy group.
Much of the corn grown in this country — more than 60 percent, according to National Corn Growers Association statistics released last year — becomes animal feed.
“The number of crops that are genetically modified grown throughout the world are increasing exponentially, but there’s very limited data on what happens ‘downstream,'” Apgar said.
“There are a few rat studies, three swine studies, a couple of studies on feedlot steers, but none of them are as comprehensive as our work. We’re taking a total systems approach, looking at every aspect of a single animal — meat, fecal material, blood, digesta — at different ages.”
Using a transgenic corn developed at SIUC but not available commercially, Apgar and his graduate students first showed that pigs digested both regular and modified corn in pretty much the same way.
When they looked for evidence of the gene in the pigs’ stomach contents and feces, they found nothing.
“That didn’t tell us where it went — just that it was no longer in the digesta,” Apgar said.
I guess the question for me becomes: Do I want this stuff in my body? and if I don’t how can I avoid it because it seems like its in everything…
Here are some tips on avoiding GMO and GM foods, check them out here.
Beginning text via wikipedia