Sunday, June 29, 2008

What Is Genetic Engineering?

 
What Is Genetic Engineering?

Genetic engineering refers to a set of technologies that are being used to change the genetic makeup of cells and move genes across species boundaries to produce novel organisms. The techniques involve highly sophisticated manipulations of genetic material and other biologically important chemicals.

Genes are the chemical blueprints that determine an organism's traits. Moving genes from one organism to another transfers those traits. Through genetic engineering, organisms are given new combinations of genes—and therefore new combinations of traits—that do not occur in nature and, indeed, cannot be developed by natural means. Such an artificial technology is radically different from traditional plant and animal breeding.

Novel organisms

Nature can produce organisms with new gene combinations through sexual reproduction. A brown cow bred to a yellow cow may produce a calf of a completely new color. But reproductive mechanisms limit the number of new combinations. Cows must breed with other cows (or very near relatives). A breeder who wants a purple cow would be able to breed toward one only if the necessary purple genes were available somewhere in a cow or a near relative to cows. A genetic engineer has no such restriction. If purple genes are available anywhere in nature—in a sea urchin or an iris—those genes could be used in attempts to produce purple cows. This unprecedented ability to shuffle genes means that genetic engineers can concoct gene combinations that would never be found in nature.

New risks

Contrary to the arguments made by some proponents, genetic engineering is far from being a minor extension of existing breeding technologies. It is a radically new technology for altering the traits of living organisms by inserting genetic material that has been manipulated by artificial means. Because of this, genetic engineering may one day encompass the routine addition of novel genes that have been wholly synthesized in the laboratory.

Novel organisms bring novel risks, however, as well as the desired benefits. These risks must be carefully assessed to make sure that all effects—both desired and unintended—are benign. UCS advocates caution, examination of alternatives, and careful case-by-case evaluation of genetic enginering applications within an overall framework that seeks to move agricultural systems of food production toward sustainability.

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