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Creating New Proteins in a Lab -- Good For Your Health?The classical understanding of why a GM crop might create new allergies is that the imported genes produce a brand new protein. The novel protein may trigger reactions.
This was demonstrated in the mid 1990s when soybeans were outfitted with a gene from the Brazil nut. Scientists attempted to produce a healthier soybean, but ended up with a potentially deadly one. Blood tests from people who were allergic to Brazil nuts showed reactions to the beans.7 Fortunately, this soy never went to market.
The GM variety that is planted in 89% of U.S. soy acres gets its foreign gene from bacteria (with parts of virus and petunia DNA as well). We can't know in advance if the protein produced by bacteria, never before part of the human food supply, will provoke a reaction.
As a precaution, scientists compare the new protein with a database of proteins known to cause allergies. The database lists the proteins' amino acid sequences that have been shown to trigger immune responses.
According to criteria recommended by the World Health Organization (WHO) and others, if the new GM protein contains sequences found in the allergen database, the GM crop is not to be commercialized and additional testing should be done.
Sections of the protein produced in GM soy are identical to known allergens, but the soybean was introduced before the WHO criteria were established, and the recommended additional tests were not conducted.
What If Bizarre Genes Start Transferring To Humans ...
If this protein in GM soybeans is causing allergies, then the situation may be made much worse by something called horizontal gene transfer (HGT). That's when genes spontaneously transfer from one species' DNA to another. While this happens often among bacteria, it is rare in plants and mammals.
But the method used to construct and insert foreign genes into GM crops eliminates many of the natural barriers that stop HGT from occurring. The only published human feeding study on GM foods ever conducted on GM foods showed that parts of the gene inserted into GM soy ended up transferring into the DNA of human gut bacteria.
Furthermore, the gene was stably integrated and it appeared to be producing its potentially allergenic protein. So, years after people stop eating GM soy, they may still be exposed to its risky protein, which is being continuously produced within their own intestines.
Sent: 02/08/2007
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