What Is a Genetically Modified Organism? Why and How Are Foods and Animals Modified?

What is a genetically modified organism (GMO)?

Genetically modified organism is a term for any living thing whose DNAhas been altered using genetic engineering. It may be a plant, animal (including humans) or bacterium, usually modified to confer a desired trait such as larger fruit or drought resistance. These genetically modified organisms are generally abbreviated as GMOs.

New ways of adding or removing genes for particular traits in plant and animal DNA continue to be sought and discovered. In other words, genetic engineering and biotechnology are changing the food we eat and the world we live in.

Della Penna, a plant biochemist at Michigan State University, believes genetically engineered foods are key to a wave of advances in agriculture and health. He describes their potential: “With genetic engineering methods, you can produce allergen-free wheat, soy and peanuts; vaccinated bananas; and add plant oils loaded with therapeutic compounds to foods for people at risk of various diseases.”

While DellaPenna and others see great potential in these new biotechnology products, others see uncertainty and even danger .

Critics of genetically modified organism (GMO) initiatives fear that genetically engineered products are being marketed before their effects are fully understood . Such concerns resurfaced with reports about taco shells containing genetically modified corn not approved for human consumption.

In North America and Europe, the value and impact of genetically modified food crops have been intensely debated.

What are genetically modified foods and who eats them? What do we know about their benefits and risks? What might genetically engineered plants do to the environment and farming practices worldwide? Can they help feed and protect the health of the world’s growing population?

Question: Who eats biotech foods?

Answer: Most likely, all of us.

Most people in the United States do not realize they have been eating genetically engineered foods since the mid-1990s. On United States supermarket shelves, including pizza, chips, cookies, ice cream, salad dressing, corn syrup and baking powder, processed foods in more than 60 percent of cases contain genetically modified soybeans, corn and canola.

Over the past decade, countries producing genetically modified food used in these processed products have grown to include South Africa, Australia, Germany, Spain, Argentina, Canada and China among 13 countries. Genetically modified food has expanded to large amounts of crops planted across these 13 countries on 130 million acres (52.6 million hectares). On United States farmland, the area planted with genetically modified crops was, in 1996, 3,6 million acres (1,5 million hectares), rising in 2001 to 88,2 million acres (35,7 million hectares), a 25-fold increase.

Question: How long have we been genetically modifying our food?

Answer: Longer than you might think.

Genetic modification is not new. Humans have been changing the genetic makeup of plants for centuries, saving them over many years and replanting them in later years to make them sweeter, more abundant and longer-lasting in storage. In this way, we transformed the wild tomato Lycopersicon from small and dry into large and juicy. From a grass called teosinte with centimeter-long “ears,” we developed foot-long (0,3 meters) ears of sweet white and yellow corn. Over the past few decades, plant breeders used traditional techniques to produce wheat and rice varieties with higher grain yields. They also created hundreds of new crop varieties using irradiation and mutagenic chemicals.

But the new genetic engineering technique differs greatly from traditional breeding. Traditional breeders transfer tens of thousands of genes between similar genetic structures. Today’s genetic engineers, in contrast, transfer a few genes between unrelated species.

Genetic engineers can take a desired gene from almost any living organism and place it in another. They can add a gene that enriches lettuce in vitamin C, or transfer a gene from the cecropia plant to fruits such as apples, pears and quinces to protect against fire blight (bacterial spoilage). The goal is the same: transfer a desired characteristic from an organism possessing it to an organism lacking it. If a gene inserted into an apple plant provides resistance to this bacterium, it could help apple growers save millions of liras annually.

Scientists call organisms produced by transferring genes between species transgenic . Several dozen transgenic food products are already on the market, including varieties of corn, squash, canola, soybeans and cotton. Most were designed to help farmers with centuries-old agricultural problems: weeds, insects and diseases.

Farmers spray herbicides to kill weeds. Biotechnological crops may carry special tolerance genes that allow them to withstand chemicals killing almost any kind of plant. Some biotech varieties, through gene transfer, have made their own insecticide using a gene from the common bacterium Bacillus thuringiensis (BT).

Other food crops, such as squash and papaya, have been genetically modified to resist disease. Scientists have recently experimented with potatoes, altering their genes with those of bees and moths to protect crops against blight fungi, and making grapevines with silkworm genes to resist insect-transmitted Pierce’s disease.

Through new genetic engineering, scientists have created transgenic animals . Atlantic salmon grow more slowly in winter, but salmon “blended” with modified growth hormone genes from other fish reach market size in half the normal time. Scientists also use biotechnology to insert genes into cows and sheep so their milk can produce a desired compound. None of these transgenic animals has yet reached the market.

Question: Are biotech foods safe for humans?

Answer: Yes, as far as we know.

Risks exist throughout our food supply. Approximately a hundred people die each year from peanut allergies. We minimize risks by rigorously testing genetically modified foods.

According to Eric Sachs, spokesperson for Monsanto, a leading developer of biotechnology products: “Transgenic crops undergo more testing than other foods we eat. We investigate potential toxins and allergens. We examine whether transgenic plants contain protein nutritional value substantially equivalent to conventional plants.”

In the United States, 3 federal bodies regulate genetically modified crops and foods: the United States Department of Agriculture (USDA), Environmental Protection Agency (EPA) and Food and Drug Administration (FDA). FDAreviews data voluntarily submitted by companies on allergens, toxicity and nutrient levels. If tests show new foods are not substantially equivalent to conventional foods, they must undergo further testing. Last year, the agency proposed tightening review of engineered foods, making safety assessments mandatory rather than voluntary.

In the mid-1990s, a biotechnology company began a project to insert a Brazil nut gene into soy. The selected gene makes a protein rich in essential amino acids. The aim was a more nutritious soybean for animal feed. Because Brazil nuts were known to contain an allergen, the company also tested the product for human reactions, considering that transgenic soybeans could accidentally enter human food. When tests showed people would react to the modified soybeans, the project was abandoned.

For some, this proved that the testing system for genetically modified foods worked. But for some scientists and consumer groups, it heightened fears of allergens and created food insecurity. Scientists know that certain proteins, such as those in Brazil nuts, can cause allergic reactions and how to test these allergenic proteins. However, a new protein with allergenic properties could exist in a traditionally produced food and remain undetected.

Often overlooked in debate about these foods’ health effects is a possible health benefit . Under some conditions, corn genetically engineered for insect resistance could improve safety for human and animal consumption. Insect-damaged corn contains high levels of fumonisin (toxins made by fungi carried on insects’ backs and growing in damaged corn). Laboratory tests have linked fumonisins to cancer in animals and concluded they may potentially cause cancer in humans. For example, people eating large amounts of corn in parts of South Africa, China and Italy have high rates of esophageal cancer, which scientists associate with fumonisins. Research shows that most biotech (genetically modified) corn has lower fumonisin levels than conventional corn damaged by insects.

Should genetically modified foods be labeled? Professor Marion Nestle, head of Nutrition and Food Studies at New York University, says she believes consumers have the right to know and choose . However, no processed food in the United States currently carries a label, because the FDA has found none substantially different from conventional foods.

Question: Can biotech foods harm the environment?

Answer: It depends on whom you ask.

Most scientists agree: the main safety issue with biotechnology products concerns the environment, not humans . Allison Snow, a plant ecologist at Ohio State University, says, “We let GMOs out of the bag before looking at actual long-term data, and now we cannot call them back.”

Proponents of biotech crops argue that the plants offer an environmentally friendly alternative to pesticides that pollute groundwater and harm wildlife. Using genetically modified organisms has significantly reduced pesticide use on cotton crops.

What might these genetically altered plants do to the creatures visiting them—non-target organisms? Concerns that built-in insecticides could harm wildlife were refuted by a study report in 1999 suggesting that genetically modified corn pollen harmed monarch butterfly caterpillars.

Monarch caterpillars do not feed on corn pollen, but on leaves of milkweed plants often growing in and around cornfields. Cornell University entomologists showed in the laboratory that genetically modified corn pollen deposited dust on milkweed leaves, and some monarch caterpillars eating them became stunted or died. For some environmental activists, this confirmed that genetically engineered crops were dangerous to wildlife.

Rick Hellmich, an entomologist with the Agricultural Research Service, argues that biotech crops may not be responsible for this effect and emphasizes that caterpillars are also exposed to other chemical insecticides that kill insects in fields.

Many ecologists believe the most damaging environmental effect of biotech crops could be unnatural gene flow . Could genetically modified plants cause harmful weeds to develop? Could transgenes conferring resistance to insects, disease or harsh conditions give weeds a competitive advantage, allowing rapid growth?

When pollen is carried by wind, bees and other pollinators, genes pass from plants to weeds. There is no doubt that transgenes will move to nearby plants. However, because natural gene flow generally occurs only between closely related species, it is unlikely to create troublesome weeds.

Given the risks, many ecologists believe testing should become broader and more rigorous, and governments should strengthen regulatory systems to better address environmental effects. Each transgenic organism brings different potential risks and benefits. Yet currently only one percent of biotechnology research funding goes to risk assessment.

Question: Can biotech foods help feed people worldwide? Can they solve hunger?

Answer: There are obstacles to overcome.

“There are 800 million malnourished people on this planet,” says Channapatna Prakash, an agricultural scientist originally from India.

For Prakash and many other scientists, genetic engineering can help solve urgent problems of food shortages and hunger. It can increase crop productivity and offer disease-resistant varieties. It could allow crops to grow even on land unable to support agriculture because of drought, depleted soils, excess salt or high aluminum and iron levels.

Some critics of genetic engineering argue that solving hunger and malnutrition lies in fair distribution of existing food supplies. Prakash agrees there is enough food worldwide. “But fair redistribution will not happen,” he says. “Protesting biotechnology on political grounds out of fear of large companies’ power would be a disappointment,” he says.

People say only large companies profit from this technology. The knowledge companies develop to produce profitable crops is coming to the aid of developing countries.

Prakash says biotech crops are not a cure for world hunger. Consider white rice, for example: it contains little iron and almost no vitamin A. In 1999, a team led by Ingo Potrykus of the Swiss Federal Institute of Technology and Peter Beyer of Germany’s University of Freiburg made a breakthrough: they transferred two daffodil genes into rice plants and introduced a bacterial gene allowing production of beta-carotene, a component of vitamin A. This beta-carotene-enriched rice was called “Golden Rice.”

According to the World Health Organization, between 100 million and 140 million children worldwide suffer from vitamin A deficiency, which blinds approximately 500.000 people annually; half of these children die within the year they lose their sight. In this context, Marion Nestle says: “Eating golden rice alone will not substantially reduce vitamin A deficiency. When people already have inadequate fruit and vegetable nutrition, beta-carotene is not converted into vitamin A.”

According to Beyer, golden rice is at least four years away from distribution. Field trials and safety studies sought by opposing groups could lengthen this period.

Question: What comes next?

Answer: Proceed carefully.

We will see together whether biotech foods fulfill their promises to eliminate world hunger and save lives. Their potential is enormous, but they still carry risks. We may pay for mistakes or accidents in ways we cannot foresee. However, the greatest mistake would be to support or reject them blindly . We should carefully analyze and weigh how, how much and why genetically modified products are made. If we test them properly on a broad scale, we can discuss their benefits versus harms.