The FDA Is Cracking Down on the Doctor Marketing 3-Parent Babies

John Zhang, a New York fertility doctor, wanted to push the boundaries of science and fertility by giving women at risk of passing on serious genetic conditions a chance at healthy kids through an IVF technique that uses the DNA of three people. But on Friday, regulators at the Food and Drug Administration issued a warning: Zhang, they said, would not be allowed to move forward with the procedure. At least, not if any part of it took place in the United States.

The IVF technique in question involves replacing the teeny amount of mitochondrial DNA in an embryo with DNA from a donor in order to prevent mitochondrial diseases from being passed down by a mother. It’s known as the “3-parent baby technique” because, technically speaking, it creates an embryo with three genetic “parents.”

Last fall, Zhang made headlines when his clinic announced that for the first time, a baby had been born using the procedure. To produce a 3-parent baby, Zhang relied on a tricky legal work-around. Because implanting a genetically-modified embryo is illegal in the US...