Genetically Modified Food for Thought


Science in Society (SiS) is proud to feature the winners of the "Integrated Graduate Program in the Life Sciences (IGP) Science and Society Class Distinction Award." Written as part of a course on science and society, these papers were chosen to be published on SiS. This month, we present the following piece by graduate student Eliza Vakana.

Whether you are for or against genetically modified (GM) food, it’s likely inevitable that you’ll consume it. Why? Soybean and corn seeds that have been genetically modified make up 90% and 80% respectively of the total seeds on the market! Large percentages of sugar cane, canola, and sugar beets are genetically modified as well, and GM crops serve as feed for the majority of our country’s livestock. 

But what does “genetically modified” mean, exactly? If a crop is considered GM, then targeted changes have been made to the seed’s genetic material, or DNA, resulting in a “better” variety. Before we had the ability to manipulate an organism’s DNA, a somewhat similar result was accomplished over time when a farmer chose a plant that seemed to be doing better—for example, producing bigger fruit than another—and bred it to a plant of the same variety. This way, that positive characteristic, or trait, would be conserved. Now, scientists can pinpoint the desired gene and artificially insert it from like organism to like organism—from corn seed to corn seed, for example. We call this kind of genetic modification cigenesis (cis=same + genesis=beginning).

Modern techniques also involve transgenesis (trans=different + genesis=beginning), a process by which the desired genetic material from one type of organism gets incorporated into a different type of organism. For example, many crops have been genetically modified to include a helpful gene found in a common soil bacterium, Bacillus thuringiensis.  This gene produces a protein that kills certain insects, but is not harmful to the plants or to humans.  Both cisgenesis and transgenesis have accelerated the time taken by conventional methods to produce the “preferred” organism.

Seeds can be genetically tailored to produce a number of desired affects, including faster growing time and larger fruit. One of most beneficial new traits is herbicide resistance, which allows the farmer to use a specific, stronger herbicide, but in a smaller quantity. This way, the herbicide won’t harm the plant and, as opposed to generic herbicides that must be used in larger quantities, less will end up in the water supply and potentially harm humans. Scientists have engineered plants that produce substances to kill the viruses and fungi that can infect them as well, making the plants disease resistant.

The elimination of certain food allergies is another exciting prospect. In research studies, scientists have been successful in removing the allergenic protein from soybeans. Others are now working to achieve a similar result in peanuts, to which at least three million people in the United States alone are allergic.

GM foods might also offer unique solutions for international health issues. For example, enriched crops such as “golden rice”—a variety of rice engineered by the company Syngenta to produce more vitamin A and iron—may provide a solution for malnutrition in countries in a famine crisis. Researchers are also studying how foods could be modified to include edible vaccines, such as the Hepatitis B vaccine, which would allow consumers to “eat” the vaccine instead of being injected.

While these modifications are exciting, there are several issues that must be considered as GM foods become more and more common throughout the United States and the rest of the world.

For many consumers, one issue is safety. The United States Food and Drug Administration (FDA) recommends that developers of new GM foods consult with the FDA on appropriate safety testing before bringing a new food to market, and bioengineered foods are subject to the same safety requirements as other, non-engineered foods. Many argue that DNA-based bioengineering is actually safer than the selective breeding methods that have been employed for centuries, as it affords scientists more control over which traits are being introduced. However, given that this is a relatively new technology, studies on the health effects of GM foods over a consumer’s lifetime have not been conducted.

Additionally, GM foods are not required to be labeled explicitly as such unless the genetic modification has significantly altered the nutritional make-up of the product or introduced an allergen, which is most often not the case. This has been a controversial issue for consumers, as many processed foods on grocery store shelves – some estimates are as high as 70% – contain GM corn or soybeans derivatives, like high-fructose corn syrup and vegetable oil. 

In addition to safety, there are also socioeconomic and political consequences of GM food to be considered. Currently, a single company, Monsanto, based in the US, controls 90% of the transgenic seeds worldwide, leaving companies such as DuPont, Syngenta and Bayer controlling the other 10%. According to their competitors, the alleged monopolistic and anti-competitive practices of Monsanto have had major implications for farmers and consumers, as the seed prices keep increasing to match, according to Monsanto, the increasing yield and efficiency provided. This leads to a subsequent increase of transgenic product prices. Higher prices are also a problem for farmers who prefer using non-transgenic seeds, as these are becoming less and less available.

The potential impact of GM foods on the environment is another important issue. Biodiversity—the variety of life in the ecosystem—could be threatened by continued genetic modification. Biodiversity is crucial for many reasons, one of which is disease susceptibility. For example, if all the crops planted in one area are genetically identical—known as monoculture—they would all be susceptible to the same diseases, making it easy to wipe out an entire population.

Also, genetic modifications could affect not just the GM crops themselves, but other plants around them. In the case of herbicide resistance, some weeds may also develop a resistance to the herbicide used, and this trait could be selected for by nature. Over time, this results in the formation of what are called “superweeds,” or weeds that can no longer be killed by the common herbicides.

All of these issues—economic, health, safety and environmental—are important to consider, both by individuals and governments, as science advances and GM food becomes even more widespread. It will depend on the collective input of the community, legislators, and scientists to determine what uses of GM foods are acceptable, and whether pros outweigh the cons.



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