Core Viewpoint - The article discusses a groundbreaking study published in the New England Journal of Medicine (NEJM) that reports the birth of eight healthy "three-parent babies" through mitochondrial donation, which offers hope for families affected by mitochondrial diseases [2][3][11]. Group 1: Mitochondrial Diseases and Their Treatment - Mitochondrial diseases, caused by pathogenic mutations in mitochondrial DNA (mtDNA), primarily affect high-energy organs such as the heart, brain, and muscles, often leading to severe health issues and lack of effective treatments [2][5]. - The technique involves transferring the nucleus of an egg from a mother with pathogenic mtDNA into a donor egg that has had its nucleus removed, allowing for the birth of children without the mother's mitochondrial diseases [5][7]. Group 2: Birth of "Three-Parent Babies" - A total of 22 women with pathogenic mtDNA mutations underwent mitochondrial donation treatment, resulting in the successful birth of eight children (including a set of twins), with the oldest being over two years old and the youngest under five months [16]. - Among the eight children, five have shown no health issues, while others experienced minor, treatable conditions, indicating initial success in preventing mitochondrial diseases [16][18]. Group 3: Ethical Considerations and Future Outlook - The technique raises significant ethical questions and has been the subject of intense debate, leading to the UK being the first country to legislate and regulate mitochondrial donation for clinical use [9][20]. - Despite the promising results, researchers urge caution due to the small sample size and short follow-up period, as some children still carry low levels of maternal pathogenic mtDNA, necessitating further long-term studies to confirm safety and efficacy [20].