In Japan, 6.3% of children from elementary school to high school suffer from food allergies, with chicken eggs being the most common culprit.
“Mom, I want a cookie!”
This simple request from three-year-old Mukuge Tomoki to his mother, Erika, is something she cannot fulfill. Tomoki is severely allergic to eggs, a fact Erika discovered when he was about ten months old. Sweets containing eggs caused rashes around his mouth, and even tiny amounts of egg later triggered vomiting and hives. Tests confirmed a severe egg allergy, with the potential for fatal reactions.
The family’s lifestyle has drastically changed since the diagnosis. Erika meticulously checks ingredient labels when shopping and cooking, as manufacturing changes can introduce eggs into previously safe foods. With Tomoki now able to open the refrigerator himself, Erika’s vigilance is more crucial than ever.
“I would be very happy if we could share delicious foods and feelings together,” Erika says.
A survey by the Consumer Affairs Agency in the 2021 fiscal year found that one-third of people with food allergies are allergic to chicken eggs. In response, Hiroshima University and Kewpie, a major Japanese food manufacturer, are researching the development of non-allergenic eggs.
Egg allergies stem from several proteins, most of which can be neutralized by heating, except for a protein called ovomucoid. Using genome editing, researchers have successfully removed this protein by targeting its specific gene in the DNA sequence. After seven years of research, they produced chickens without the ovomucoid protein in 2020. By 2023, they verified that these eggs were safe and that genome editing had not affected other genes.
A clinical trial is now underway at Sagamihara National Hospital in Kanagawa Prefecture to test if children with egg allergies can safely consume these eggs. The trial involves a powder made from heated eggs that lack ovomucoid. Tomoki participated, consuming an amount equivalent to one twenty-fifth of an egg, a quantity that would typically cause a reaction. After two hours of monitoring, he showed no allergic symptoms.
Erika is hopeful about the future. “I want to eat eggs,” Tomoki says excitedly. “I want to crack open an egg and make a fried egg.”
Dr. Ebisawa Motohiro, who leads the clinical trial, believes this technology could eventually help with other food allergies, such as those caused by milk, wheat, tree nuts, and peanuts. The hospital plans to test the technology on about 60 people by spring 2026 to ensure its safety.
Meanwhile, researchers are developing a menu of items using these allergen-reduced eggs. Although these eggs tend to be slightly firmer when heated, ongoing tests aim to improve their texture.
Kodama Daisuke, from Kewpie’s research and development division, is committed to the project. “We want to keep trying so children who have never eaten eggs can enjoy the same treats as other youngsters,” he says. One of the planned menu items is pudding.
