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2 Controversies over genetic modification 3 Evidence for environmental impact 4 References 5 External links |
Both the terms GE (Genetically Engineered) and GMO (Genetically Modified Organism) are commonly used to refer to all organisms that have added genes from another species which were inserted through the techniques of genetic engineering.
Phrases such as "Genetically Damaged Food", "Genetically Diseased Food Substitutes", or "Frankenfood" are sometimes heard.
Genetic modification is the subject of controversy in its own right - some believe that the science itself should be forbidden, but such people are rarely trained in genetics.
Proponents of genetic modification argue that it allows great advances in agriculture (for instance, making plants more tolerant of certain diseases or of water shortages, increasing their nutrient value, or decreasing their cost of production), as well as allowing other beneficial creations such as the petroleum-eating bacteria.
Opponents generally argue that the ultimate results of releasing genetically modified organisms are not predictable and may have unexpected and irreversible effects on the environment; however, no adverse effects have been noted in 50 years of using radiation-mutagenized wheat. Since genetically modified organisms, like conventional organisms, are patentable under some laws (such as the U.S. law), GMO crops can theoretically harm agriculture itself, by leaving independent farmers unable to purchase seed each year.
These concerns have varying impact, depending on particular national circumstances. Some argue that the patent issue is not necessary valid in developed nations as some hybrid crops seeds (already eligible for patents) are likely to be purchased anyway (e.g. [maize|corn).
Proponents typically dismiss published concerns as bad science and alarmism. They state that genetic modification offers enormous benefits in terms of improved agricultural efficiency and the resulting beneficial health effects of better nutrition.
Opponents typically point to the many unstudied issues and warn that mistaken assumptions about biosafety could result in disaster. This controversy is many years from being resolved.
The practice of genetic modification as a scientific technique is unrestricted in the United States; individual GMO crops (such as soya) are subject to intense study before being brought to market and are common in the United States and estimates of their market saturation vary widely. Many countries in Europe have taken the opposite position: that genetic modification has not been proven safe, and therefore that they will not accept genetically modified food from the United States or any other country. This issue has already gone before the World Trade Organization, which determined that not allowing GMO food into the country created an unnecessary obstacle to international trade. Consequently, genetic modification within agriculture is an issue of some strong debate in the United States, the European Union, and some other countries.
It is almost certainly true that not all genetic modifications have the same effects on health or on the environment; those policies that classify all genetic modifications as good or bad are thus overgeneralized. However, indefinite postponement of policy decisions may not be in the public interest.
Besides, those arguing for application of the precautionary principle insist one of the risks of using GMO is that of natural species being contaminated by GMOs (for example, natural canola acquiring the new GMO canola genes through cross-pollination). They fear natural non transformed species could be led to disappear (due to the genetic selective advantage of the transformed species), resulting in loss of biodiversity. Yet this has not happened with common wheat, massively and randomly modified genetically by radiation.
The standard agricultural practice of applying certain (but not all) pesticides to crop plants has been alleged to result in short- and long-term harmful effects in humans. There is therefore some question as to whether genetically-modified crops that confer pest resistance might be harmful to humans as well. Current pest-resistant strains use a relatively innocuous organic toxin derived from the bacterium Bacillus thuringiensis (Bt). However, harmfulness is an area of great controversy not only among the general public, but among scientists as well.
Opponents often falsely present research conducted by scientists at the Imperial College London and the Universidad Simon Rodrigues in Caracas, Venezuela as revealing that the diamondback moth grew 56% faster when fed cabbage genetically modified to contain Bt than it did when fed cabbage without the Bt. This is not very honest, as the moths were fed on leaf discs treated with Bt, not transgenic plants. Therefore, the research has just as much potential relevance to organic farming, in which Bt is a commonly used pesticide, as it does to transgenic plants. The 56% figure is disingenuously picked because it is the largest number that can be derived from the data; the differences in pupal weight, development time, and pupal weight/developmental time are much, much smaller.
There is already some strong evidence that the cultivation of a genetically modified plant may lead to environmental changes. However, whether a genetically modified plant can itself harm the environment is a matter of controversy among scientists.
For example, the overproduction of insecticide in a transgenic population induces a heavier selective pressure on insects, hence leading to further resistance to the insecticide in the insect population and reducing the effect of this pesticide when applied to non-GMO crops. In Australia, the Agriculture department noticed that the parasite of the cotton plant, supposed to be killed by the GMO cotton Ingard was proliferating.
Another impact is noticed upon the use of GM plants resistant to herbicides, such as Roundup.
Seventy-one percent of genetically engineered crops planted in 1998 are designed to be resistant to herbicides such as glyphosate, the active ingredient in Roundup. Roundup, is the world's most widely used herbicide (112,000 tonnes of glyphosate was used world-wide in 1998).
The United States Department of Agriculture (USDA) statistics from 1997 show that the use of Roundup Ready soybeans (GM-roundup-resistant) resulted in a 72% increase in the use of glyphosate.
Terminology
Controversies over genetic modification
Evidence for environmental impact
Increase resistance to insecticides
Increase resistance to herbicides
References
External links