By Nat Graham. Nat Graham is a sixth year doctoral candidate in the Division of Biological Sciences at the University of Missouri Columbia. His research focuses on improving genetic transformation in maize. He is also the founder of a local program called “Science on Tap”, designed to give graduate students the opportunity to present their research to the community.
The potato is the United States’ most frequently consumed vegetable, so we discussed GM potato ‘101’ with PhD student Nat Graham, a sixth year doctoral candidate in the Division of Biological Sciences at the University of Missouri Columbia. Nat shed some light on how genetic modification is being used in potato growing operations across the country.
GMO Answers: When we talk about GM potatoes, what is genetically modified about them?
Nat Graham: When most people think about genetic modification, they assume that the product has been engineered to produce something new, but in the case of GM potatoes it’s actually the opposite. In this case, the plant has been engineered to actually make less of something that it is already producing. Using a technology called RNAi, scientists are able to tell the plant to stop making substances that can lead to undesirable traits.
The only GM potato you can currently purchase is known as the White Russet potato, and it has been engineered by potato pioneer, J.R. Simplot Company, to have two new traits. The first reduces browning and bruising that can occur when the potato is being packaged, stored and transported, or even cut in your kitchen. While the browning is merely a cosmetic issue, it still leads to plenty of food being unnecessarily thrown away each year. Additionally, when being processed, any cut potatoes usually have additives added to prevent them from browning during transport. The White Russet will stay white, hence the name, even if subjected to harsh handling conditions or being cut during processing, leading to less food waste and additives.
The second trait reduces the amount of a naturally occurring chemical called asparagine. When asparagine is subjected to high heat, such as that used in fryers, it can be converted into acrylamide, a probable carcinogen. By reducing the amount of free asparagine in the potatoes, they can be fried without the worry of producing harsh by-products.
While not currently available for purchase, Simplot has also received approval for other GM potato varieties. In addition to reducing browning and acrylamide, these potatoes are resistant to late blight, the disease responsible for the Irish potato famine. They also have a slower conversion of starch to sugars, enabling cold storage to extend quality.
GMO Answers: How much of the United States’ potato crop is genetically modified?
Nat Graham: The only GM potato that is available to consumers and restaurants is the White Russet, and it is a very new product. As a result, only a very small amount of acreage has been devoted to it so far. The company worked with farmers to grow approximately 6,000 acres of the potato to be sold in 2017. By comparison, there were over 955,000 acres of potato planted in the U.S. in 2015.
GMO Answers: Why would farmers choose to grow genetically modified potatoes?
Nat Graham: The choice of which product to grow is completely up to individual farmers, so I can’t speak for them. I can say, though, that after talking to plenty of farmers myself, they are interested in selling more usable potatoes instead of those that are bruised during harvest and storage. They also want to spray less pesticide when possible to combat diseases such as late blight.
GMO Answers: How did the GM potato come to be?
Nat Graham: The process of making any genetically engineered plant is generally pretty similar. A DNA sequence is identified that is thought will improve the plant quality. That DNA sequence is then inserted into the plant using a modified version of a naturally-occurring bacterium called Agrobacterium. The plant is then grown in a lab and tested to ensure that it contains exactly the sequence the scientists originally designed. From there it is moved to a greenhouse where it is can be propagated. Plants can then be grown in the field to perform further testing. Then, more experiments are done to ensure that the plant performs exactly like the non-modified version. In the case of the White Russet, testing was performed to ensure it reduced browning and produced less asparagine, but they also tested in commercial conditions across all potato growing states to ensure they weren’t more susceptible to diseases, had the same nutritional content as conventional counterparts, and weren’t likely to produce an allergen.
Once Simplot was sure that the product was as safe and nutritious as their conventional counterparts, they filed for regulatory approval. In the U.S. this means going through the U.S. Food and Drug Administration (FDA), the U.S. Department of Agriculture (USDA), and the Environmental Protection Agency (EPA). Each agency has its own testing and safety requirements that must be satisfied in order to gain “non-regulated status”. However, it isn’t done there either. Simplot is also seeking regulatory approval in common U.S. export markets for potatoes. In the case of the White Russet, this means getting approval form at least the agencies in Canada, Japan, and Mexico.
GMO Answers: What’s your favorite potato product?
Nat Graham: We eat quite a few potatoes in my house, most are purchased fresh from the grocery and cooked at home. I’ve been known to seek out a fast-food French fry from time to time though!
*The J. R. Simplot Company reviewed this post for accuracy.