The new technique, which is still in development and not yet ready for use in humans, is a special variation on IVF that uses a donor egg cell with healthy mitochondria into which the nuclear DNA from a mother with diseased mitochondria is implanted. Normal in vitro fertilisation with the father’s sperm takes place, resulting in an embryo for implantation that is biologically the child of the two parents, but with small amounts of mitochondrial DNA from a third person, the egg donor. This prevents the birth of children with the severe disabilities that result from defective mitochondria.
A recent Human Fertilisation and Embryology Authority (HFEA) consultation found broad public support for the idea implanted (see previous news) and no evidence to suggest health risks associated with the procedure. Prof Dame Sally Davies, chief medical officer for England, has now said: "It's only right that we look to introduce this life-saving treatment as soon as we can", acknowledging that there were sensitivities around the technique but that she remained "personally very comfortable" with it. Critics fear the use of the technique, which was developed in the UK and would be expected to be used for around ten couples a year, could be a step towards more general genetic modification becoming part of routine IVF.
Draft regulations on the use of three-person IVF will be published this year for further public consultation, with voting on a final version expected to take place in Parliament in 2014.