Japanese scientists have succeeded in genetically engineering chickens that lack a major allergen based on genome-editing technology, a breakthrough that could lead to the development of less allergenic eggs.

The team of researchers, primarily from the National Institute of Advanced Industrial Science and Technology (AIST) and the National Agriculture and Food Research Organization, said the finding will also help improve the safety of vaccines and other drugs produced using fertilized eggs.

“There are other allergens, so our findings will not directly lead to the resolution of all the problems associated with egg allergies,” said Isao Oishi, a senior scientist at AIST. “But we revealed that not only the safety of hen eggs can be enhanced, but various practical applications, such as the quality improvement of fowl meat, will likely be realized with genome-editing technology in the future.”

Genome editing is a technology that destroys and replaces specific genes.

However, because chicken eggs undergo rapid cell division during the 24-hour period between fertilization and egg laying, it was difficult to manipulate genes of the eggs with genome-editing technology.

The team then adopted a method in which chicken cells that develop into sperm cells were modified using the technology.

The researchers first eliminated from the sperm cells a gene that produces ovomucoid, a protein that causes a strong allergic reaction. Then they transplanted the modified cells into fertilized eggs and hatched them.

The team succeeded in creating chickens that completely lack the allergy-causing gene by successfully breeding the genetically manipulated fowl.

The findings were published in the British scientific journal Scientific Reports on April 6.