Foreign genetic material is ingested with food
The opponents of genetically modified foods also argue that the inclusion of "foreign" genetic material is dangerous in their opinion. The proponents hit back with the argument "proteins are broken down in the stomach or intestines". Apparently neither side is right. This was proven by the German scientists W alter Doerfler and Rainer Schubbert in their work at the Institute for Genetics at the University of Cologne in a paper that appeared in the January 30, 1998 edition of the "wiener clinical weekly publication". What the scientists did: In the laboratory, mice were fed the genome of bacteriophages of the M13 strain. Bacteriophages are similar to viruses except they infect bacteria. The genome of these "parasites" is completely different from that of mice. But contrary to the assumption that the genetic material of the phages (DNA) would be completely broken down in the digestive tract of the test animals, the DNA was finally found in the cells of these mice.
The scientists comment: "Experiments with M13 bacteriophage DNA fed to mice show that a few percent of the M13 test DNA survives passage through the gastrointestinal tract in the form of fragments." The foreign DNA then passes through the intestinal wall into white blood cells as well as spleen and liver cells.
Similar results were also obtained in experiments on pregnant mice: parts of the genetic material of M13 were found - apparently transported via the placenta - in "individual cells of fetuses and newborns in a wide variety of organ systems, but so far never in all cells of a new one mouse generation." The effects of cancer development or the development of malformations caused by foreign DNA have not yet been investigated, as Doerfler and Schubbert found.
But the German scientists do not want the results to be understood as a plea against genetic engineering and its applications in medicine and agriculture. "Foreign deoxyribonucleic acid (DNA) is part of our ecosystem. Significant amounts of foreign DNA from a wide variety of sources are continuously ingested with food," they write.
It is remarkable that at a time when many people are afraid of genetically engineered food, science is getting indications that the absorption of foreign DNA into the organism is nothing unusual. The geneticists: "For millions of years, humans and their ancestors have been exposed to an uncountable combination of genes from plant and animal foods."
It is therefore urgently necessary to inform the public about biological issues. The subject itself should be compulsory in every school and in every training path. This should enable people to better assess biological and medical problems associated with genetic engineering.
