Your mother may have given you her eyes, but she could have also given you mitochondrial DNA that carries disease-causing mutations. A study in mice shows that two techniques can drastically reduce the amount of this potentially harmful DNA in eggs and embryos, thus potentially sparing children from the illnesses. The methods could provide alternatives to a controversial mitochondrial replacement procedure that would result in so-called three-parent embryos.
Although researchers have not yet tested the method in human embryos, the work “is unprecedented,” says molecular biologist Mikhail Alexeyev of the University of South Alabama in Mobile, who wasn’t connected to the study. “It’s the first time this has been done in an embryo.”