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Methods and Genetic Engineering

  1. Economics and Economic Methods
  2. ENGINEERING AS A PROFESSION
  3. FAMOUS PEOPLE OF SCIENCE AND ENGINEERING
  4. GENETICALLY ENGINEERED PRIZE FISH CAUSE CONCERN
  5. Methods And Measures
  6. Methods of fingerprint detection

Genetic engineering, as done so far, means the artificial insertion of one or a few genes into the DNA of the recipient organism. This is fundamentally different from what happens in conventional breeding. 1. The insertion may occur in the middle of gene and thereby disrupt the genetic code of the recipient organism. 2. The inserted gene is also very likely to disturb the action of neighbouring genes. 3. The inserted gene will produce a new protein that may often be alien to the recipient organism.

All these three disturbances may disturb the metabolism of the cell more or less seriously so that new, unexpected substances that may be toxic or allergenic may be produced. This has also been found in a number of cases indicating that the consequences may be dangerous.

As none of the genetically engineered foods on the market today has undergone testing that is even close to the rigorous assessment required to ensure safety for the world population, it is necessary to immediately stop the production and trade with these products until they have undergone the necessary testing. But even so a residual risk remains that some harmful substance will pass undetected.

Proponents of genetic engineering of foods have been maintaining that there is no important difference between this technology and breeding. Therefore they argue that it is unjustified by authorities to treat these products differently than natural or conventionally bred foods. Consequently it is argued that engineered foods that are "substantially equivalent" to their natural counterparts should be treated in the same way as natural foods by the legislation.

It is therefore most important to critically scrutinise different arguments that are used to justify the above position.

First, however, let us define genetic engineering and breeding.

Genetic engineering means the artificial insertion of one or a few genes into the genome of a host organism. This allows genes from completely alien species to be introduced.

Conventional breeding means the combination of hereditary traits by natural mating procedures.

There are fundamental differences between breeding and genetic engineering. Contrary to breeding, genetic engineering means random insertion of a sequence of genetic codes into active DNA, disrupting the precise sequence of genetic codes of the host and disturbing the functioning of neighbouring genes. This may give rise to unexpected and potentially toxic or allergenic molecules. Or the nutritional value may be altered.

Most importantly, genetic engineering is capable of introducing into an organism genetic information from very distant species. There is no body of existing information upon which to base prediction regarding how such divergent genetic information will affect the functioning of the recipient organism. This increases tremendously the risk of unanticipated side-effects from such manipulations.

Since many of the genes now being introduced into food-producing organisms are derived from organisms that have never been part of the human food supply we have no way of knowing how humans will respond to the effects of these genes on the food and whether such food is appropriate for our species. They may be allergenic or toxic to humans or they may disturb the metabolism, giving rise to toxic or allergenic molecules.

Extensive experience from toxicology shows that even the most rigorous safety assessment methods may fail to detect unexpected harmful molecules.

Because of the fundamental difference between these technologies and especially because the unique aspects of genetic engineering brings with it the risk of emergence of new, unexpected molecules, some of which may be harmful and difficult to detect, it is scientifically unjustified to equate foods produced by genetic engineering with natural or conventionally bred foods in legislation concerning safety aspects.

Labelling of all foods and food ingredients that are genetically engineered is absolutely necessary in order to make it possible to trace, as early as possible, unexpected harmful effects of genetically engineered foods.

Source: Living Earth. Режим доступа: http://www.psrast.org/mianbree.htm

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