Mitochondrial Gene Therapy Passes Final U.K. Vote

The United Kingdom’s House of Lords has approved legislation to allow a new type of in vitro fertilization (IVF) that would replace faulty DNA, preventing certain types of genetic diseases. The vote follows the House of Commons approval of the measure on 3 February, making the United Kingdom the first country to explicitly allow the procedure, which would combine DNA from two biological parents and an egg donor.

The technique will be allowed under fairly tight regulation: Researchers who wish to offer the service to couples still must apply for and receive a license from the country’s Human Fertilisation and Embryology Authority.

The technique, called mitochondrial DNA replacement therapy, would allow women who have mutations in the DNA of their mitochondria, the organelles that provide chemical energy for cells, to have genetically related children who don’t carry the mutations. It is controversial, however, because it would modify the DNA of an embryo in a way that could be passed on to future generations.

People who have faulty mitochondria can experience a variety of symptoms, including heart problems...