A View from Doug Gurian-Sherman
Are GMOs Worth the Trouble?
Many are eager to trot out GMOs as the answer to our food problems. But lower-tech alternatives work better.
You hear a lot these days about genetically modified organisms, with many people arguing that they’ll be a necessity in the not-so-distant future, as climate change stresses agriculture, and as a growing, and increasingly affluent, population consumes more food, and more inefficient animal-based foods. Others argue that we’ll need GMOs to reduce global warming emissions, harm to biodiversity from pesticides, pollution from fertilizers (such as coastal “dead zones”), and overuse of scarce resources like fresh water by industrial agriculture. You might have seen one such argument a few months ago from David Rotman, the editor of MIT Technology Review, in his feature called “Why We Will Need Genetically Modified Foods.”
But all these arguments rest on certain assumptions, and these assumptions are flawed, at best. Rotman, for example, argued that we’ll need GMOs because simpler, less controversial options such as breeding are simply too slow. He thinks breeding doesn’t give growers access to enough genetic diversity to allow adaptation to climate challenges and to sufficiently increase yields.
Many breeders and molecular biologists disagree. As pointed out by the many authors of a recent paper in Nature, we have barely scratched the surface of the genetic potential of crop species. Research on many major crops over the past 20 years such as wheat and its relatives has shown that current widely grown crop varieties use only a small fraction of available genetic potential. The so-called “yield plateau” of the last several decades in some crops is more likely due to complacency and reduced funding after the green revolution rather than deficiencies in breeding potential.
And while it’s true there have been advances in GMO technology in recent years, it’s also true that there have been advances in breeding technologies, such as genomic methods that may speed the breeding process in some cases. For example, when a flood tolerance gene was identified in an obscure rice biotype, the use of marker technology led to improved rice varieties in about five years, rather than the typical 10 to 15.
Some argue that the development of GMOs saves time—another questionable assertion. It typically takes 10 or more years to develop a genetically engineered trait—a time-frame similar to breeding. This fact was also recently acknowledged by a Monsanto executive. GMOs require years of field testing to ensure that the gene functions as expected, with no nasty surprises for farmers, under the varying conditions that a crop will face after commercialization.
While breeding continues to meet important challenges like improving drought tolerance, improving nitrogen fertilizer efficiency, or increasing yield, genetic engineering has contributed little or nothing. For example, there is now one variety of genetically modified corn, tolerant to moderate drought, which would improve overall productivity by a total of only about 1 percent in the United States. By contrast, breeding and agronomy have improved corn drought tolerance by about 1 percent per year over the past three decades. And recent years have seen the development through conventional breeding of many drought tolerant varieties of corn, cassava, rice, wheat, millet, and sorghum.
None of this means that GMOs won’t make some contributions that improve crop resilience, efficiency, or productivity. But that is different than establishing the need for GMOs, especially when all the current evidence suggests that breeding is more effective overall.
And let’s not forget that there are solutions to our food issues that have nothing to do with genetics. Genetic improvements must be designed to complement agroecologically based farming systems to adequately address the challenges facing agriculture. By contrast, GMOs (and many conventional crop varieties) have been designed for use in unsustainable industrial monoculture farming systems. Prominent environmental scientist Jonathan Foley of the University of Minnesota concluded in a recent article that “While future genetically modified crops could add other beneficial plant traits, which might help boost productivity in crucial crops, I think the best answers lie elsewhere.” He pointed to several non-genetic alternatives, including reducing food waste (which accounts for about 30 to 40 percent of current food production), reducing our consumption of animal products, and reducing the amount of food crops used for biofuels.
There are yet other ways to improve agriculture. Crop rotations, largely abandoned by industrial agriculture, typically increase yields by 20 or 30 percent. Water holding capacity of soil can be improved, and susceptibility to drought lessened, by planting cover crops that increase soil organic matter. Such methods can greatly reduce water pollution from nitrogen and the need for pesticides.
Backers of GMOs also tend to downplay the unresolved challenges of the technology. One such challenge is the high economic concentration of the seed industry, facilitated by gene patents. Current uses of the technology also seem to encourage the expansion of industrial monoculture farming, with all its problems. And most of the pipeline for GMOs is more of the same—herbicide resistant crops that will exacerbate pesticide use.
It’s also worth noting that there’s no real consensus on GMO crop safety. Although many of the crops may well be benign, some could be harmful, prompting unresolved questions about the adequacy of current regulations.
And let’s consider the opportunity costs in pursuing GMOs. Money invested in GMOs is money that won’t go into the often cheaper and better solutions discussed above, and which are currently greatly underfunded.
The point is that the so-called “need” for GMOs that we hear about from some circles isn’t really an adequately supported assertion. We still have a lot to learn about the possible benefits as well as the dangers of GMOs. And it’s important to remember that we have many better alternatives that are far from played out.
Doug Gurian-Sherman is a senior scientist in the Food and Environment Program at the Union of Concerned Scientists, a nonprofit science advocacy group.
Become an MIT Technology Review Insider for in-depth analysis and unparalleled perspective.Subscribe today