EcoHearth: Come Home to the Earth

Would you eat a plant that had a gene from a bacteria added to it? Would you favor advancements in agriculture that could help relieve world hunger and save millions of lives? These are two of the extreme sides of the debate over the use of GE seeds, considered by proponents as part of the “Green Revolution" capable of boundless benefits, and by detractors as “Frankenfoods” with potential catestrophic consequences.

With it now possible to move virtually any gene between any two organisms, developing new plant varieties has become increasingly high-tech. Genetically engineered (GE) seeds, also known as genetically modified (GM) seeds, offer resistance to pests, diseases and drought, as well as higher-yielding plants with greater nutritional value. Although the technology faces widespread opposition among the general public, a large business in seed technology has developed around this science. Here’s what you need to know about the pros and cons of GE seeds:

The Science of Genetic Engineering
GE seeds are made using recombinant DNA technology that combines the DNA from two different organisms. In this process, a target gene is isolated and placed in a vector—an organic vehicle used to transfer DNA between organisms. Pieces of viruses can be used as vectors, but the most common vectors are plasmids, circular loops of DNA found in bacteria. Next, duplicates of the vector are made by adding it to bacteria that will replicate it as they divide, producing millions of copies of the construct.

The vector is isolated from the bacteria and inserted into the target cell, which for multicellular organisms will be a fertilized egg. For animal cells, the vector can be directly injected into the cell’s nucleus to combine with its DNA, while for plant cells a special gun is used to “shoot” it through the cell wall into the nucleus. Once the foreign gene is inserted, the new transgenic organism will express the gene, producing whatever protein it encodes.

There are many uses for the GE technology, including

• Creating animal models of human diseases
• Using bacteria to make human insulin and other essential proteins
• Producing industrial materials—such as using cows and goats to produce the spidersilk protein that can be harvested from their milk
• Giving beneficial characteristics to plants by producing GE seeds.

GE Seeds
While many types of GE seeds have been developed, most are used for large-scale crops (such as soybeans, corn, canola and cotton) belonging to one of three categories:

• Insect-resistant plants containing a gene from the bacteria Bacillus thuringiensis (Bt) that produces a protein toxic to insects whose life-cycle includes a caterpillar stage
• Herbicide-tolerant (HT) plants resistant to the commercial herbicide Roundup®
• Plants resistant to crop-damaging viruses

Patents for Seeds
GE seeds have become a large and competitive business, and legal protection has evolved along with the science. Since 1930, the US Patent and Trademark Office (USPTO) has issued a special plant patent to protect newly developed varieties. In 1970, the US Departement of Agriculture began issuing a Plant Variety Protection Certificate (PVPC), which protects the rights of crop plants for 20 years, and those of fruit trees and vines for 25 years.

A major step for GE seeds came with a US Supreme Court decision in 1980, allowing the broader-reaching utility patent to be granted for inventions of living organisms. These utility patents added more protection than both the plant patent and the PVPCs, most notably control of the seeds produced by the plant. Thus, farmers who buy GE seeds may not be allowed to collect seeds from their crops to plant the next season.

A Growing Controversy
GE seeds promise plants resistant to pests, disease, and drought that can be used to grow more abundant and nutrious foods in more diverse areas around the world. In addition, GE seeds may reduce the environmental impact of farming by requiring less water, insectides and fossil fuels due to less need for tilling and other weed-control measures.

A major health concern of GE seeds used for food crops is that adding foreign genes could introduce new allergens, possibly triggering a reaction in some people to a food thought to be safe. Serious environmental issues include:

• GE plants spreading their foreign genes to other plants, threatening the existence of non-GE varieties
• Herbicide-tolerant plants spreading their genes to non-crop plants, creating “super weeds”
• Insect-resistant GE plants harming non-targeted organisms
• The reduction of plant biodiversity if many farmers worldwide grow the same crops.

Among other considerations are the fear that global agriculture will be controlled by the corporations that produce GE seeds and the ethical issues surrounding genetic engineering.

While GE seeds for corn, cotton and soybeans are widely used by large farms in the US, most seeds sold to the public are not GE due in part to higher cost and opposition to the technology. One of the nation’s largest seed sellers, W. Atlee Burpee & Co., does not sell any GE seeds, and many other companies have also made a point to label their products as “non GE.”

Developing novel varieties of plants is nothing new; however, genetic engineering has made it feasible to produce specialized plants not possible by normal breeding techniques. While embraced by large-scale farmers, the general public still seems reluctant to accept GE seeds. Any improvements GE seeds may offer will need to be balanced with assurances of safety, responsible use and education to better inform consumers about this intriguing, but possibly detrimental technology.

Additional resources:
USDA Biotechnology Frequently Asked Questions (FAQ)
Wikipedia: Genetically Modified Food

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