The first genetically modified crop wasn’t made by a megacorporation. Or a college scientist trying to design a more durable tomato. Nope. Nature did it — at least 8,000 years ago.
Well, actually bacteria in the soil were the engineers. And the microbe’s handiwork is present in sweet potatoes all around the world today.
Scientists at the International Potato Center in Lima, Peru, have found genes from bacteria in 291 sweet potato varieties, including ones grown in the U.S., Indonesia, China, parts of South America and Africa. The findings suggest bacteria inserted the genes into the crop’s wild ancestor, long before humans started cooking up sweet potato fries.
“People have been eating a GMO for thousands of years without knowing it,” says virologist Jan Kreuze, who led the study. He and his colleagues reported their findings last month in the Proceedings of the National Academy of Sciences.
Kreuze thinks the extra DNA helped with the domestication of the sugary vegetable in Central or South America.
Sweet potatoes aren’t tubers, like potatoes. They’re roots — swollen, puffed-up parts of the root. “We think the bacteria genes help the plant produce two hormones that change the root and make it something edible,” Kreuze tells Goats and Soda. “We need to prove that, but right now, we can’t find any sweet potatoes without these genes.”
When our ancestors started to farm sweet potatoes, Krezue says, they very likely noticed the puffed up root and selected plants that carried the foreign genes. The genes stuck around as the sweet potato spread across the globe — first to Polynesia and Southeast Asia, then to Europe and Africa.
Today, the sweet potato is the world’s seventh most important crop, in terms of pounds of food produced, the Food and Agriculture Organization of the United Nations says.
“In the U.S., it seems to be important only at Thanksgiving,” Kreuze jokes. “But in parts of Africa, it’s a staple crop. It’s very robust. When every other crop fails, sweet potatoes still grow.”
In China, sweet potatoes are used to feed livestock. And in many other places, people saute the plant’s leaves to make a yummy dish called sweet potato greens.
All these farmers — whether they’re tending to backyard plots in Rwanda or megafarms in China — are raising a natural GMO.
Continue reading at NPR.
Sweet potato image via Shutterstock.