The Quest for Super Seeds: Genetically Modified Foods
By Seth Porges
This past summer, much of the U.S. suffered through its worst drought in decades. Crops withered, fields browned, and food prices spiked.
For geneticists, the solution lies not in irrigation or greenhouses, but the nature of plants themselves. "I tell people that it would be easy to grow a drought-tolerant crop—you just have to turn it into a cactus," says Michiel van Lookeren Campagne, Ph.D., head of biotechnology at the seed and biotech firm Syngenta. "Unfortunately, a cactus does not grow very fast, so we have to look to other solutions."
Increasingly, those solutions involve genetics. While the scientists who work with human genomes get most of the headlines, the most widespread commercial application of genomics actually involves plants. In an often controversial quest to produce more and better crops, researchers have been unraveling plant DNA for decades, and using it to produce super-seeds that are resistant to pests, capable of withstanding harsh herbicides, and better able to survive droughts like the one that recently ravaged America's farmlands.
Harnessing Genes for Better Results
For as long as there have been farms, farmers have been engineering better seeds. Using little more than common sense, ancient farmers would selectively choose and cultivate seeds from their most robust and productive plants, giving their stock the sort of strength and yield that wouldn't naturally occur by chance.
Today, this basic idea of breeding for the best traits has moved from the field and into the lab, where researchers use computers to scan plant DNA, and high-tech equipment to modify it in order to bring out desirable traits.
"When we first started talking about this in the 1970s, people looked at me and said, 'If this is possible, why has nobody ever done it before?'" says biochemist Marty Apple, Ph.D., president of the Council of Scientific Society Presidents and an early pioneer in the field of agricultural genomics. "It's like a piece of wire that you bend into a paper clip for the very first time and you suddenly say, 'Ah ha!' No one had ever done it before, because no one had ever done it before."
|Still, it would be years before genetically modified (or GM) foods actually made it onto store shelves. In 1994, Calgene—formerly an independent company that is now a subsidiary of the biotech and seed company Monsanto—introduced the first FDA-approved, commercially available GM plant: the Flavr Savr tomato, which was designed to have a delayed ripening, and thus a longer shelf life. And while the Flavr Savr was pulled from shelves just a few years later (it wasn't very profitable), GM crops are now everywhere. According to the FDA, 93 percent of soy, 88 percent of corn, and 94 percent of cotton crops planted in 2012 were genetically modified.|
The Key Players: Computers and Bacterium
The GM process typically begins with a computer. Researchers use advanced software to scan a plant's genome for a particular gene or set of genes that they want to alter. "Finding a particular gene used to be like finding a needle in a haystack," says Brian Vande Berg, Ph.D., the trait research manager for corn at Bayer CropScience. "Corn has a ballpark of 25,000 genes, and you may only be interested in one or two of them. But using computers, you can go to those one or two very quickly."
With the target sequence identified, researchers can go back to the lab and add a new gene or set of genes that are associated with a desirable trait. And although these added genes may come from other plants, they are usually pulled from a rather surprising source. "The majority of traits that are in the products today come from bacteria," Berg says. "Almost all of the herbicide traits, and all of the insect-control traits, have come from bacteria."
Because bacteria tend to be simpler organisms than plants, it is much easier to completely scan their genetic sequence in search of a particular gene. And because the planet has an astounding variety of bacterial species, the catalogue of potential DNA donors is essentially endless. "If you're looking for a gene that does something really unusual, there are so many bacteria to choose from, and just a limited number of plants to choose from," Berg says.
Researchers now use bacteria—in particular a type called Agrobacterium—as their preferred tool for getting new DNA into a crop. Agrobacterium happens to be naturally good at transferring DNA from itself to a plant. In nature, this allows it to act as a disease, infecting plants with foreign DNA that often produces tumor-like growths. But in the lab, scientists have found that they can piggyback on this ability in order to transfer beneficial DNA.
"Prior to using Agrobacterium, much of the DNA introduction in corn was done using a gene gun—think of it as a high-tech nail gun—to physically insert DNA into a plant cell," says Todd Jones, a research director at the biotechnology and seed company DuPont Pioneer. "However, this method took a lot more trial and error."
Genetically Modified Foods: Controversy Crops Up
You can't talk about GM food without talking about the controversy. On one side: GM critics who decry so-called "Frankenfruits" as unlabeled, untested, and possibly unsafe intrusions into food supply. On the other: supporters who point out that GM foods have now been on shelves for a number of years without any real safety issues.
There's also the potential environmental impact: Critics question the effects of foreign DNA on plant ecosystems and whether herbicide-resistant crops could cause farmers to use more poisonous weed-killers. Others counter that insect-repellent crops need to be sprayed with fewer pesticides, and drought-resistant crops can grow while tapping less of the water supply.
Whatever one's position, GM crops are the new norm. Over the past half-decade, public attention to and media coverage of the topic has plummeted, even while use of the crops has skyrocketed. Gallup last polled the public's views on GM crops in 2005—the result was an even split, with 45 percent in support, and 45 percent opposed—and the Pew Charitable Trust's Initiative on Food and Biotechnology, a project that billed itself as an "honest broker" on the topic, shut its doors in 2007. It would seem that in the U.S., the conversation is essentially over—or at least quieted down. Today, most Americans either aren't aware of the prevalence of GM food, or simply take it for granted. "This is because the industry has a long history of safe use," Berg suggests. "The industry has done a good job of only selling safe products."
What the Future Holds
Sometime around the year 2050, the United Nations expects the world population to tip past the 9 billion mark. "As the world population continues to grow and the number of arable acres remains stagnant, farmers need to do much more with less to meet productivity demands," Jones says. That, in a nutshell, is the great hope of genomics in agriculture: not just that it can create farmer-friendly products that are capable of withstanding insects or long stretches on store shelves, but that it can help us squeeze more food out of limited soil space.
There are also initiatives to make crops—particularly those aimed at malnourished populations in the developing world—more nutritious. The best known example is "Golden Rice," genetically engineered to use added beta-carotene as a tool against the widespread problem of Vitamin A deficiency. (It should be noted that the product is currently not being used anywhere for human consumption due to a variety of health and environmental concerns.) In 2010, the FDA approved its first GM crop designed to have modified nutritional content: a soybean developed by DuPont Pioneer to reduce saturated fat content by using higher levels of oleic acid, a "good" monosaturated fat.
And then there are droughts like the one that laid waste to fields across the U.S. this past summer. Because water deprivation affects a plant in so many different ways, there is no single genetic solution to this problem. So while progress has been made in creating crops that can tolerate a bit less water—Syngenta has a corn variety that purports to produce a 15 percent greater yield in dry conditions, and DuPont Pioneer has a corn crop that claims a 5 percent yield improvement—the pursuit of totally drought-proof stock is still in its infancy. In fact, much of the current generation of seeds was actually produced using traditional cross-breeding techniques to bring out drought-resistant traits, not genetic engineering.
But biotech companies are paying close attention to the growing world population and the omnipresent risk of another dry season, and a new wave of genetically engineered drought-resistant seeds should be hitting farms in the near future. And if they work as well as farmers hope, the farm landscape could be changed forever.
"Finding ways to grow crops that are drought-tolerant is particularly challenging, but we're making progress with both native trait programs and genetically engineered solutions that are very promising," Syngenta's Campagne says. "We hope to have those new engineered products to market in the second half of this decade."
Seth Porges is a journalist, editor, and columnist whose work has appeared in Popular Mechanics, Bloomberg News, BusinessWeek, Men's Health, PC Magazine, and many other publications.
This disclosure applies to the following T. Rowe Price mutual funds: T. Rowe Price Blue Chip Growth Fund, T. Rowe Price Capital Appreciation Fund, T. Rowe Price Capital Opportunity Fund, T. Rowe Price Growth Stock Fund, T. Rowe Price Health Sciences Fund, T. Rowe Price Mid-Cap Growth Fund, T. Rowe Price New America Growth Fund, T. Rowe Price New Horizons Fund, and T. Rowe Price Tax-Efficient Equity Fund. Monsanto represented 0.81% of the T. Rowe Price Blue Chip Growth Fund, 0.51% of the T. Rowe Price Capital Opportunity Fund, 0.67% of the T. Rowe Price Health Sciences Fund, 1.85% of the T. Rowe Price New America Growth Fund, and 0.75% of the T. Rowe Price Tax-Efficient Equity Fund as of June 30, 2012. It was not held by the other funds above. Bayer represented 0.34% of the T. Rowe Price Health Sciences Fund as of June 30, 2012 and was not held by the others listed above. Syngenta and DuPont were not held by the funds above as of June 30, 2012. The funds' portfolio holdings are historical and subject to change. All mutual funds are subject to market risk, including possible loss of principal. This material should not be deemed a recommendation to buy or sell any of the securities mentioned.
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