A controversial technique that uses DNA from three parents has resulted in the first-ever birth of a child, a team of American scientists in Mexico confirmed Tuesday.

The technology allows parents with rare genetic mutations to have healthy babies and, while not approved in the United States, is legal in the United Kingdom.

New Scientist reported that the baby, a boy, was born five months ago to Jordanian parents. The child was at risk of inheriting a severe neurological disorder called Leigh syndrome, which typically kills individuals within a few years of birth.

In using DNA from three individuals, researchers were able to remove some of the mother’s DNA from an egg and leave out the disease-causing DNA. The healthy DNA was slipped into a donor’s egg, which was then fertilized. Thus, the child inherited DNA from his two parents and the egg donor.

Dr. John Zhang, of the New Hope Fertility Center in New York, who led the team that carried out the technique, told New Scientist, “To save lives is the ethical thing to do.”

Zhang’s findings are detailed in the journal Fertility & Sterility.

Dusko Ilic of King’s College London, who wasn’t involved in the work, told New Scientist that the feat is “great news and a huge deal.”

“It’s revolutionary,” he told the website.

The Associated Press contributed to this report.