Genetic modification is different from traditional cultivation and breeding. It is often argued that GM is not different – but it is, because unnatural recombinations are created. Genetic material is recombined between species for which there is no, or very low, probability of natural progeny. While this technique is relatively simple, it could lead to destabilising effects for the modified organism. The introduction of genes triggers profound changes within the plant or animal species. The latter could react to the modification with unpredictable effects. This is the most serious scientifically based arguments against large-scale, commercial use of the first-generation GMOs – the unpredictability with regard to where in the recipient cell chromosomes’ insertion of vector DNA takes place.
GM may result in the emergence of new viruses. The most usual way to genetically modify an organism is to insert the new gene with some other genetic material, called a promoter. The promoter’s goal is to guide the new gene towards the desired effect. The added hereditary sequence often comes from viruses and can be rejected and transferred to other places on the genome, other cells or even other organisms – it could activate genetic sequences containing latent viruses of the genome.
Due to the instability generated through the insertion of the gene and the hereditary material, these viruses may move into other living beings, including humans, and evolve into dangerous forms.
The following is taken in part from Twin (Third World Network) ‘GMO risks and hazards: Absence of evidence is not evidence of absence of risk’.
In order to increase milk production in cows, a genetically engineered bovine growth hormone (BGH) was injected into cows. Manufacturers of BGH claimed it was identical to the natural product, but it was subsequently demonstrated by independent research that epsilon-N-acethyllysine was substituted for lysine in the engineered hormone – such amino acid substitution may have unpredictable consequences for the conformation and function of proteins, and recent research indicates that milk from BGH treated cows may contribute to increased breast cancer in humans.
Tobacco plants were genetically engineered to produce gamma-linolenic acid, but instead the plants produced mainly the toxic product octadecatetraemic acid which is not contained in unmodified tobacco plants.
When yeast was modified to obtain increased fermentation, it was unexpectedly found that the metabolite methyl-glyoxal accumulated in toxic and mutagenic concentrations.
When a gene from Brazil nut was inserted in soybean plants, unexpected strong allergic reactions were recorded in people with nut allergies. These people had not had any allergic reaction to soybeans in the past. The inserted gene did not code for any known allergen.
In order to gain increased levels of the amino acid L-tryptophan, a bacterium (Bacillus amyloliquefaciens) was genetically engineered. This amino acid has widespread application in tablets as a nutritional supplement. What was found with the genetically engineered amino acid placed in tablets, was that the tablets contained small accounts of a toxic trypothan related molecule. It has not been clarified (because the genetically modified stock of bacteria was not available for investigation) whether this was the cause of EMS (esinophilia-myalgia syndrome) which resulted in 37 deaths and 1500 cases of chronic neurologic and autoimmune symptoms.