Researchers in the U.K. have reported the successful birth of eight healthy babies using mitochondrial donation and pronuclear transfer to prevent mitochondrial DNA diseases. This three-person IVF technique involves replacing the mutated mitochondrial DNA of the mother with healthy mitochondrial DNA from a donor egg, resulting in embryos with nuclear DNA from the parents and mitochondrial DNA from a third person. The babies, including a set of identical twins, show normal development and no signs of mitochondrial disease to date. The studies were published in The New England Journal of Medicine and represent a significant advancement in reproductive medicine. However, the approach remains controversial and is legally permitted in limited countries.