As home gardeners in the U.S. page through seed catalogs and pick out their favorite heirlooms, there’s a new seed that has never been available to them before: a tomato the color of a concord grape with plum-colored flesh. It looks otherworldly, maybe Photoshopped. But it’s not. This nightshade is purple because its creators at Norfolk Plant Sciences worked for about 20 years to hack color genes from a snapdragon flower into the plant. The genes not only provide pigment, but high levels of anthocyanin, a health-promoting compound.
This dusky fruit, called the Purple Tomato, is the first genetically engineered food crop to be directly marketed to home gardeners-the seeds went on sale Saturday. Until now, genetically engineered foods were generally only made available in the United States to commercial producers; last year, a handful of small farmers started growing and selling the tomatoes.
Through direct sales to gardeners, Norfolk expects to change American perceptions about GMO foods. According to a 2020 Pew Research study, most Americans think GMOs are worse for their health compared to a food that does not have any genetic modification; only 7% perceive them to be healthier than other foods.
“We’ll try to prove by this product and by the company that there is so much benefit that can go to consumers through biotechnology, better taste, better nutrition prime examples,” says Nathan Pumplin, the CEO of Norfolk Healthy Produce, a subsidiary of Norfolk Plant Sciences.
The lead scientist behind the Purple Tomato is biochemist Cathie Martin, who was trained at the University of Cambridge. About 20 years ago, she decided to work on a transgenic tomato using DNA from another unrelated organism, in this case, a purple snapdragon-an edible flower.
The goal was to develop a tomato with high levels of anthocyanins, the compounds that give blueberries and blackberries, eggplant and purple cabbage their color and their status as superfoods.
Anthocyanins have been shown to have anti-cancer and anti-inflammatory effects. They are powerful antioxidants. Such chemicals help neutralize unstable molecules in the body, called free radicals, that can damage healthy cells and are linked to aging and disease.
“It’s normal for tomatoes to make these healthy antioxidants. They typically don’t make them very much in the fruit, though,” Pumplin says, explaining that they normally appear in the stems and leaves. “So what Cathie [Martin] did was put the on switch into tomato.”
She started with the basic technique that scientists figured out in the 1980s using a bacteria to naturally insert its DNA into host organisms.
It is something which can occur naturally. A good example of such a plant is the sweet potato: it contains DNA from the agrobacterium and through the technical definition is transgenic-a plant containing genetic material of two different organisms.
Martin isolated the gene in the snapdragon flower responsible for its purple hue. She then collected that gene and introduced it into bacteria. The tomato could then take up this foreign genetic material and turn on the new gene.
“It really is a great example of understanding how the natural world functions and building on that to meet our needs,” Pumplin says.
The result? Norfolk’s purple tomato packs the same anthocyanin punch per weight as does a blueberry or eggplant, says Pumplin. What’s more, since Americans eat so many tomatoes, this innovation makes nutritional benefits more accessible.
In a study published in Nature, Martin discovered that mice who consumed a diet including purple tomatoes lived 30% longer than those who didn’t.
Related posts:
Gardeners can now grow a genetically modified purple tomato made with snapdragon DNA
Purple GMO tomato now available in the US
Get Ready to Grow Purple Tomatoes This Summer
