The goal was to prevent the child from inheriting a fatal genetic disease from the mother. The birth, of a boy, is revealed in a research summary published by the journal Fertility & Sterility. Scientists are scheduled to make a fuller presentation at a meeting next month.
The magazine New Scientist said the baby was born five months ago to Jordanian parents, and that they were treated in Mexico by a team led by John Zhang of the New Hope Fertility Center in New York. The technique is not approved in the United States, but Zhang told the magazine, “To save lives is the ethical thing to do.”
The child was at risk of inheriting DNA for Leigh syndrome, a severe neurological disorder that usually kills within a few years of birth. Only a minority of Leigh syndrome cases are inherited through the type of DNA that is targeted by the new method.
The technique involved removing some of the mother’s DNA from an egg, and leaving the disease-causing DNA behind. The mother’s healthy DNA was slipped into a donor’s egg, which was then fertilized. As a result, the baby inherited DNA from both parents and the egg donor.
The technique is sometimes said to produce “three-parent babies,” but the DNA contribution from the egg donor is very small.
People carry DNA in two places, the nucleus of the cell and in features called mitochondria, which lie outside the nucleus. The technique is designed to transfer only DNA of the nucleus to the donor egg, separating it from the mother’s disease-causing mitochondrial DNA.
The research summary identified the mother as a 36-year-old woman and said her pregnancy was uneventful. One of the five eggs the researchers treated was suitable for use.
Critics question the technique’s safety, saying children would have to be tracked for decades to make sure they remain healthy. And they say it passes a fundamental scientific boundary by altering the DNA inherited by future generations. Mitochondrial DNA is passed from women to their offspring.
Still, last year, Britain became the first country in the world to allow creation of human embryos with the technique. In the U.S., a panel of government advisers said earlier this year that it’s ethical to test the approach in people if initial experiments follow certain strict safety steps.
That report was requested by the Food and Drug Administration, which is currently prevented by Congress from considering applications to approve testing the technique in people.
Shroukhrat Mitalipov, who has worked with the approach at the Oregon Health & Science University in Portland, said that given the panel’s conclusion, “We believe it’s time to move forward with FDA-approved clinical trials in the United States.”
Henry Greely, who directs the Center for Law and the Biosciences at Stanford University, said Tuesday he sees nothing wrong with using the technique if it is safe and is aimed at diseases clearly caused by faulty mitochondrial DNA.
Dieter Egli of the New York Stem Cell Foundation, who has done work in the area, was cautious about the implications of the new report.
“I wouldn’t go out there at this point and tout the accomplishment because we don’t have enough information,” he said Tuesday. “We do not know exactly what was done.”
“We have to wait” for a fuller report, he said.
The child is not the first to inherit DNA from three people. In the 1990s, some children were born after researchers used a different technique. But federal regulators intervened, and the field’s interest now has passed to the new approach.