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MSU Plant Researchers Explain the Basics of Genetically Modified Organisms

Plow on farm of wheat

An online search for “GMO” returns more than 88 million results — a tangled mess of frightening images, dense data, skepticism, insulting comments and conflicting claims and counterclaims. For the average consumer, separating reputable sources from propaganda is tough, if not impossible.

What is a genetically modified organism, or GMO?

Even the answer to the question can be controversial.

At its most basic, genetic modification is the process by which changes occur in an organism’s genome. Nature is perpetually modifying the genetics of every organism in an effort to help the organism adapt to its changing environment.

“It’s important to understand that all organisms — not just those that are the basis of foods — are genetically modified in some way, shape or form,” says Brad Day, a professor and associate department chair for research in Michigan State University’s Department of Plant, Soil and Microbial Sciences. “They are genetically modified by persisting in the environment. Radiation from the sun can induce changes in the genome, for example.”

The Origins of GMOs

More than 30,000 years ago, humans realized they could have a hand in the process of modifying genes when they domesticated and began selectively breeding wolves to ensure the animals passed along specific characteristics. Humans also have bred plants for thousands of years in an effort to ensure the survival of desirable traits.

While conventional selective breeding methods are still the most common, the newer biotechnology techniques used to create GMOs are actually rooted in genetic engineering. Scientists use biotechnology to insert one or more genes from one organism into another to give the second organism the specific trait controlled by the transferred gene or genes.

Adding a gene that promotes drought resistance, for instance, may permit farmers to grow a crop in a nontraditional region of the world or in an area with dwindling water resources.

In 1973, scientists Herbert Boyer and Stanley Cohen created the first genetically engineered organism — E. coli bacteria that had the gene for resistance to the antibiotic tetracycline transferred into it. Once the pair demonstrated that the organisms could pass the added trait to subsequent generations, interest in genetic engineering ballooned.

Farmers who became early adopters of genetically modified crops did so primarily to save money. Insect-resistant crops needed fewer pesticide applications, and herbicide-resistant crops made weed control easier and more effective.

“Genetic engineering is a technology used in several disciplines, but food has been by far the most controversial [use],” says Day. “Changes in the genome may include input traits — something that helps the grower manage the crop better in response to insects, diseases or weeds. There are also output traits — things that might improve yield, delay flowering times or enhance a plant’s ability to produce a nutritional element such as a vitamin.”

Today, GM varieties of 10 crops have been approved for sale by the federal government and are commercially available in the United States. Corn, soybeans and cotton represent the vast majority, and roughly 90 percent of those crops produced in the U.S. are GM varieties. The other approved GMO crops are varieties of squash, papaya, alfalfa, sugar beets, canola, the Innate potato and the Arctic apple.

Are GMOs safe?

The most debated topic related to GMOs is whether they threaten the health of humans or the environment. Critics often call GMOs “unnatural” and “dangerous.” Researchers like Rebecca Grumet, a professor in the MSU Department of Horticulture, point out that safety questions also can arise with conventional breeding, since plants make toxic substances on their own.

“Modification through genetic engineering is not unsafe simply because it’s genetic engineering,” says Grumet. “In terms of alterations to a plant’s genome, what’s important is not the method that was used. It’s what genes or traits have been introduced. The idea behind genetic engineering is that it’s more precise, and it lets scientists take advantage of traits present in a given species to better another.”

Internationally renowned organizations, including the American Medical Association, the National Academy of Sciences and the World Health Organization, have deemed GMOs safe. Rigorous testing throughout the process of trait development and ensuing research have led scientists to reach the same conclusion.

“Hundreds of independent research studies have shown that there are not greater risks associated with GM crops,” says Grumet. “There is scientific consensus on this topic, despite the controversy.”

Are GMOs necessary?

Conservative estimates suggest that the human population will surpass 9 billion by 2050. The actual figure could be closer to 10 billion. Either way, this will require a massive boost in food production to feed that many people. Crops that are more adaptable to varying climate conditions and less vulnerable to pathogens and other pests will be significant pieces of the puzzle.

“We can’t control the fact that the population is increasing or that there is a finite amount of agricultural land — land that is decreasing in quality overall,” says Day. “When you’re talking about feeding 9 billion or 10 billion people by 2050 with crops that won’t get wiped out by pests and diseases, we don’t have the luxury of feeding everyone from a backyard garden. Some people have fears about large-scale industrial agriculture and GMOs, and that’s why we should also be looking at things from the viewpoint of sustainability.”

Cholani Weebadde, an assistant professor in the MSU Department of Plant, Soil and Microbial Sciences and associate director of the World Technology Access Program, spends much of her time assisting developing countries with capacity building. A plant breeder and international agriculture expert, Weebadde is uniquely suited to speak about GMOs with political and agency leaders.

“In my opinion, it’s important that countries have functional regulatory systems in place so they can make science-based, informed decisions on commercializing GM crops and products so farmers have access to the best technologies,” says Weebadde. “Having transparent systems in place with evaluations conducted using a risk-based approach is important for countries and their ability to say yes or no to the technologies.”

Pests and diseases aren’t the only concerns driving the development and use of genetically modified crops. Climate change also is making farming more challenging worldwide. According to Weebadde, some food crops are naturally ill-equipped to handle the added environmental stresses, ranging from not enough rain to unyielding cold spells.

“Since we are dealing with narrow genetic and germplasm bases for most of our staple food crops, we may have to reach out to genetic engineering technologies and genes from other sources to improve them further,” she says. “Otherwise, we may run out of options.”

Adapted from a story by Cameron Rudolph published in Futures, a magazine produced twice a year by Michigan State University AgBioResearch. Read past issues of Futures at www.futuresmagazine.msu.edu.

 

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