Selective breeding and genetic engineering
Selective breeding and genetic engineering are "both used for the improvement of human society." However, selective breeding is a much longer and more expensive process than genetic engineering. It takes genetic engineering only one generation of offspring to see and study improvement as opposed to selective breeding where many generations are necessary. Therefore, it costs more to observe many generations.
Selective breeding is known as the natural way to engineer genes while genetic engineering is more advanced, technical, scientific, complex and is inevitable in out future.
What are the dangers?
Many previous technologies have proved to have adverse effects unexpected by their developers. DDT, for example, turned out to accumulate in fish and thin the shells of fish-eating birds like eagles and ospreys. And chlorofluorocarbons turned out to float into the upper atmosphere and destroy ozone, a chemical that shields the earth from dangerous radiation. What harmful effects might turn out to be associated with the use or release of genetically engineered organisms?
This is not an easy question. Being able to answer it depends on understanding complex biological and ecological systems. So far, scientists know of no generic harms associated with genetically engineered organisms. For example, it is not true that all genetically engineered foods are toxic or that all released engineered organisms are likely to proliferate in the environment. But specific engineered organisms may be harmful by virtue of the novel gene combinations they possess. This means that the risks of genetically engineered organisms must be assessed case by case and that these risks can differ greatly from one gene-organism combination to another.
So far, scientists have identified a number of ways in which genetically engineered organisms could potentially adversely impact both human health and the environment. Once the potential harms are identified, the question becomes how likely are they to occur. The answer to this question falls into the arena of risk assessment.
In addition to posing risks of harm that we can envision and attempt to assess, genetic engineering may also pose risks that we simply do not know enough to identify. The recognition of this possibility does not by itself justify stopping the technology, but does put a substantial burden on those who wish to go forward to demonstrate benefits.
Fundamental Weaknesses of the Concept
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Imprecise Technology—A genetic engineer moves genes from one organism to another. A gene can be cut precisely from the DNA of an organism, but the insertion into the DNA of the target organism is basically random. As a consequence, there is a risk that it may disrupt the functioning of other genes essential to the life of that organism. (Bergelson 1998)
Side Effects—Genetic engineering is like performing heart surgery with a shovel. Scientists do not yet understand living systems completely enough to perform DNA surgery without creating mutations which could be harmful to the environment and our health. They are experimenting with very delicate, yet powerful forces of nature, without full knowledge of the repercussions. (Washington Times 1997)
Widespread Crop Failure—Genetic engineers intend to profit by patenting genetically engineered seeds. This means that, when a farmer plants genetically engineered seeds, all the seeds have identical genetic structure. As a result, if a fungus, a virus, or a pest develops which can attack this particular crop, there could be widespread crop failure. (Robinson 1996)
Threatens Our Entire Food Supply—Insects, birds, and wind can carry genetically altered seeds into neighboring fields and beyond. Pollen from transgenic plants can cross-pollinate with genetically natural crops and wild relatives. All crops, organic and non-organic, are vulnerable to contamination from cross-pollinatation. (Emberlin 1999)
Health Hazards
Here are the some examples of the potential adverse effects of genetically engineered organisms may have on human health. Most of these examples are associated with the growth and consumption of genetically engineered crops. Different risks would be associated with genetically engineered animals and, like the risks associated with plants, would depend largely on the new traits introduced into the organism.
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