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Tomatoes are common in daily life. Cathie Martin, a British scientist, has been working on developing purple tomatoes for years. Though the color is unusual, now this special kind of tomatoes, which has gained approval from the US government, has very high levels of antioxidants(抗氧化剂).

Antioxidants, also known as AOS, are found naturally in plants like blueberries and red cabbage. Scientists believe AOS may help prevent heart disease and help fight against diseases like diabetes. But tomatoes naturally only have a small amount of AOS in them. Martin wanted to see if she could create tomatoes with lots of AOS by changing the DNA of a tomato plant.

A plant developed from specially created DNA is known as a GMO. After adding two genes(基因) from a plant called snapdragon, Martin soon found her plants were producing small purple tomatoes with lots of AOS. Martin and other scientists further tested the tomatoes on mice that were likely to get cancer. The mice that were fed the purple tomatoes lived about 30% longer than those fed normal tomatoes. Though that’s good news, experiments on mice don’t always predict what effects on humans will be like. We need to see more experiments about it.

GMOs were first allowed in America in the late 1990s. But GMO products weren’t popular with customers. Many people were scared by the idea that the foods weren’t natural or safe. There’re still questions about the effects of GMO crops on the environment. However, scientists deny these claims.

Even so, many people still have concerns about them. Because of these concerns, most GMO products created over the last 20 years have focused on helping farmers rather than attracting customers.

Anyway, on September 7, 2022, the US approved the purple tomatoes, which is the first time it has approved a GMO plant designed to target human health.