There is broad public support in the United Kingdom for allowing a new type of IVF treatment that could prevent mitochondrial diseases, the country's Human Fertilization and Embryology Authority (HFEA) announced today. The techniques would introduce new DNA into an embryo, and so it has raised thorny ethical questions. At the same time, the authority advised the government that several safeguards should be included in any proposals for new regulations that would permit clinics to perform the technique.
Mitochondria are organelles that provide cells with energy. They carry their own DNA, called mtDNA, and mutations in those genes can cause mitochondrial diseases. These have a range of symptoms and can differ in severity, but they can cause blindness, heart failure, muscular dystrophy, and dementia. The mtDNA is primarily inherited from the mother; although sperm do have mitochondria, most decay after fertilization.
Scientists have been experimenting with possible ways to replace the unhealthy mitochondria in an affected woman's egg or in early embryos. The research is ongoing, and it's not yet considered ready to try in humans. Current U.K. law prohibits the technique and any others that would place an embryo with altered DNA into a woman's body. But recent expert opinions have called for allowing the technique as an option for families who are at risk for having children with mitochondrial disease. In January 2012, the U.K. government asked HFEA, which oversees and regulates the use of gametes and embryos in fertility treatments and research, to conduct a public consultation on the techniques and provide advice on the safety and efficacy of the treatment.