GMO (genetically modified organisms) is a term most commonly used to refer to crop plants created for human or animal consumption using the latest molecular biology techniques.
These plants have been modified in the laboratory to enhance desired traits such as increased resistance to herbicides or improved nutritional content. Genetic engineering can create plants with the exact desired trait very rapidly and with great accuracy. For example, a gene responsible for drought tolerance can be inserted into a different plant. Genetically modified crops will gain drought tolerance as well. Not only can genes be transferred from one plant to another, but genes from non-plant organisms also can be used.
The best known example of this is the use of B.t. genes in corn and other crops. B.t., or Bacillus thuringiensis, is a naturally occurring bacterium that produces crystal proteins that are lethal to insect larvae. B.t. crystal protein genes have been transferred into corn, enabling the corn to produce its own pesticides against insects such as the European corn borer.
Genetically modified food has the potential to solve many of the world’s hunger and malnutrition problems, and to help protect and preserve the environment by increasing yield and reducing reliance upon chemical pesticides and herbicides. Yet there are many challenges, especially in the areas of safety testing, regulation, international policy and gmo labeling. Many people feel that genetic engineering is the inevitable wave of the future and that we cannot afford to ignore a technology that has such enormous potential benefits. When people ask, “what is gmo”, they are really asking if the benefits outweigh the concerns.
Benefits of GMO Foods
The world population has topped 6 billion people and is predicted to double in the next 50 years. Ensuring an adequate food supply for this huge population is going to be a major challenge in the years to come. GMO (also referred to as G.E.) foods promise to meet this need in a number of ways, such as creating plants that are impervious to insects/pests (so don’t require pesticides), are resistant to weed-killing chemicals, that demonstrate improved resistance to viruses, fungi and bacteria-related plant disease, improved resistant to freezing temperatures, and that can withstand long periods of drought or high salt content.
Malnutrition is common in third world countries where impoverished peoples rely on a single crop such as rice for the main staple of their diet; and rice does not contain adequate amounts of all necessary nutrients to prevent malnutrition. If rice could be genetically engineered to contain additional vitamins and minerals, nutrient deficiencies could be alleviated.
Medicines and vaccines often are costly to produce and sometimes require special storage conditions not readily available in third world countries. Researchers are working to develop edible vaccines in tomatoes and potatoes. These vaccines will be much easier to ship, store and administer than traditional injectable vaccines.
Not all GMO plants are grown as crops. Soil and groundwater pollution continues to be a problem in all parts of the world. Plants such as poplar trees have been genetically engineered to clean up heavy metal pollution from contaminated soil.
Concerns/Criticisms of GMO Foods
Concerns about GMO foods generally fall into three categories: environmental hazards, human health risks, and economic concerns.
Unintended harm to other organisms. A recent laboratory study found that pollen from B.t. corn caused high mortality rates in monarch butterfly caterpillars. Monarch caterpillars consume milkweed plants, not corn, but the fear is that if pollen from B.t. corn is blown by the wind onto milkweed plants in neighboring fields, the caterpillars could eat the pollen and perish. Unfortunately, B.t. toxins kill many species of insect larvae indiscriminately; it is not possible to design a B.t. toxin that would only kill crop-damaging pests and remain harmless to all other insects. Currently, however, the potential risk to non-target organisms is unclear and requires further evaluation.
Reduced effectiveness of pesticides. Just as some populations of mosquitoes developed resistance to the now-banned pesticide DDT, many people are concerned that insects will become resistant to B.t. or other crops that have been genetically-modified to produce their own pesticides.
Gene transfer to non-target species. Another concern is that crop plants engineered for herbicide tolerance and weeds will cross-breed, resulting in the transfer of the herbicide resistance genes from the crops into the weeds. These “superweeds” would then be herbicide tolerant as well. Other introduced genes may cross over into non-modified crops planted next to GMO crops.
Human health risks
Creation of new allergies. Many children in the US and Europe have developed life-threatening allergies to peanuts and other foods. There is a possibility that introducing a gene into a plant may create a new allergen or cause an allergic reaction in susceptible individuals.
A proposal to incorporate a gene from Brazil nuts into soybeans was abandoned because of the fear of causing unexpected allergic reactions. Extensive testing of GMO foods may be required to avoid the possibility of harm to consumers with food allergies. Labeling of GMO foods and food products will acquire new importance.
Potential negative effects on human health. There is a growing concern that introducing foreign genes into food plants may have an unexpected and negative impact on human health. However, on the whole, with the exception of possible allergenicity, scientists believe that GMO foods do not present a risk to human health.
Bringing GMO food to market is a lengthy and costly process, and of course GMO/agri-biotech companies wish to ensure a profitable return on their investment. Many new plant genetic engineering technologies and GMO plants have been patented, and patent infringement is a big concern of agribusiness. Yet consumer advocates are worried that patenting these new plant varieties will raise the price of seeds so high that small farmers and third world countries will not be able to afford seeds for GMO crops, thus widening the gap between the wealthy and the poor. It is hoped that in a humanitarian gesture, more companies and non-profits will offer their products at reduced cost to impoverished nations.