So now, here’s everything you’ve always wanted to know about GMOs but didn’t know who to ask:
What are genetically modified (or engineered) foods (or organisms)?
Genetically modified organisms (GMOs) are organisms in which the genetic material (DNA) has been altered in a way that does not occur naturally. This is called gene technology or genetic engineering as it allows selected individual genes to be transferred from one organism into another, or between non-related species (like potato and chicken gene).
Why tamper with nature?
The initial objective of this "recombinant DNA technology" is to improve crop production (for instance, producing papayas that are resistant to ringspot virus or tomato with a delayed ripening trait, or plants that are more tolerant of herbicides). Insect resistance is achieved by incorporating into the food plant the gene for toxin production from the bacterium Bacillus thuringiensis, which is safe for human consumption. On the other hand, virus resistance is achieved by introducing a gene from certain viruses which cause disease in plants.
What are the main issues of concern for human health?
• Allergenicity. While traditionally developed foods are not generally tested for allergenicity, protocols for tests for GM foods have been evaluated by the Food and Agriculture of the United Nations (FAO) and World Health Organization (WHO). No allergic effects have been found as far as GM foods currently on the market are concerned.
• Gene transfer. Gene transfer from GM foods to cells of the body or to bacteria in the gastrointestinal tract would cause concern if the transferred genetic material adversely affects human health. This would be particularly relevant if antibiotic resistance genes, used in creating GMOs, were to be transferred.
• Outcrossing. The movement of genes from GM plants into conventional crops or related species in the wild (called "outcrossing") and the mixing of crops derived from conventional seeds with those grown using GM crops, may have an indirect effect on food safety and food security. This risk is real, as was shown when traces of a maize type which was only approved for feed use appeared in maize products for human consumption in the US.
What are the issues of concern for the environment?
Current investigations focus on: The potentially detrimental effect on beneficial insects or a faster induction of resistant insects; the potential generation of new plant pathogens; the potential detrimental consequences for plant biodiversity and wildlife, and a decreased use of the important practice of crop rotation in certain local situations; and the movement of herbicide resistance genes to other plants.
Will pest-resistant plants cause pests to become super pests?
A super pest cannot be controlled or overcome, contradicting the principles of biology. The ability of a pest population to adapt to pesticides or genes used to control it is nature’s way of assuring its survival. However, even if pests develop resistance to one pesticide or gene, they are still vulnerable to new or older control mechanisms, such as a different pesticide or a remodified plant. With DNA engineering, it would be possible to rotate pest-resistant genes in a plant, modify the plant’s own resistance mechanisms, or transfer more than one pest-resistant gene to the plant, making it very difficult for pests to defeat the new resistance.
Are GM foods safe?
Different GM organisms involve different genes inserted in different ways. Which means that individual GM foods and their safety should be assessed on a case-to-case basis. GM foods currently on the international market have passed risk assessments and are not likely to present risks for human health. In addition, the consumption of such foods in countries where they have been approved has shown no adverse effects on human health.
How are GM foods regulated nationally?
In some countries, GM foods are not yet regulated. Countries which have legislation in place focus primarily on assessment of risks for consumer health. Countries which have provisions for GM foods also regulate GMOs in general, taking into account health and environmental risks.
What kind of GM foods are on the international market?
All GM crops available on the international market today have been designated using one of three basic traits: Resistance to insect damage, resistance to viral infections, and tolerance towards certain herbicides. All the genes used to modify crops are derived from microorganisms. For instance, there’s insect-resistant maize and herbicide-tolerant soybean in Argentina, Canada, South Africa, US, and European Union, or virus-resistant squash in Canada and the US.
What further developments can we expect in the field of GMOs?
Future GM organisms are likely to include plants with improved disease or drought resistance, crops with increased nutrient levels, fish species with enhanced growth characteristics, and plants or animals producing pharmaceutically important proteins such as vaccines.