Nasal sprays and eyedrops could soon be a thing of the past (Image Source/Rex Features)

Who needs antihistamines if you can eat your sneezes and itchy eyes away? Rice that could protect people against allergies such as hay fever has moved a stage closer to clinical trials, following a successful safety assessment in monkeys.

“I’d like to try this GM rice in people in the near future,” lead researcher Fumio Takaiwa of Japan’s National Institute for Agrobiological Sciences in Tsukuba told New Scientist.

None of the macaques fed the altered rice for six weeks suffered side effects, reports Takaiwa’s team. So the stage is now set for clinical trials.

Delayed release

The rice is designed to block symptoms of runny noses and sneezing in people allergic to Japanese cedar pollen, who account for 20 per cent of the Japanese population. It is genetically modified to contain the seven proteins within cedar pollen that provoke the most serious allergic reactions in people.


Once in the intestine, the proteins damp down allergic responses through so-called “oral tolerance”. This is a process, controlled by lymph nodes, by which the immune system “learns” not to overreact to harmless foreign material such as food.

To stop the proteins being digested before they can have their effect, the rice was engineered to produce them in the endoplasmic reticulum, a part of rice plant cells that passes undigested through the stomach.

In 2005, Takaiwa demonstrated in mice that the strategy works. He used a different type of rice designed to make a different set of cedar pollen proteins that cause a similar allergy in mice.

The latest version fed to the monkeys is now ready to test in humans, he says. Because monkeys, too, react to different proteins, the latest assessment was simply to look at safety. Only when he gives the rice to people will Takaiwa find out if it works or not.

Softening attitudes

Currently, doctors treat the allergy by giving patients repeated injections of tiny amounts of pollen, but this is painful for patients, inconvenient because of the necessary repeat visits to the doctor, and carries a slight risk of a life-threatening reaction.

Patients treated instead with the rice would have to eat it regularly about three to six months before the allergy season, which lasts from February to April.

If it works, Takaiwa says the principle could easily be extended to other allergies. Already, his team is working a second type of rice to treat allergy to house mites. “We got good results in mice,” he says.

Takaiwa is also hopeful that if it works, it will pave the way for other GM-based vaccines and help soften opposition to genetically modified crops. “If our rice works well, I think the atmosphere around GM food will change,” he says.

Journal reference: Journal of Agricultural and Food Chemistry (DOI: 10.1021/jf900371u)