Recently in Britain, renewed talk of banned legislation regarding advances in an in vitro fertilization (IVF) technique has commenced. The controversial procedures would save children from inheriting certain genetic diseases but would also result in a child with three genetic parents and the destruction of a fertilized egg. The new IVF techniques obviously raise ethical and legal concerns, but should Britain pass this legislation they would be the first in the world to test these procedures in humans.
Mitochondrial DNA (mtDNA) is inherited from the mother and is the source of numerous devastating neuromuscular and neurodegenerative disease. Mutations in mtDNA passed on from mother to child are responsible for diseases such as muscular dystrophy, diabetes mellitus, deafness, and myoclonic epilepsy and affect around 1 in 5000 people. Now Britain has initiated steps towards clinical trials investigating a break through IVF technique that combines the nuclear DNA of the mother with mutation-free mtDNA from a donor egg.
UK’s Human Fertilization and Embryology Authority (HFEA) announced on January 19th a public dialogue regarding this emerging IVF technique in order to gauge public opinion of the possible use in a clinical setting. The Secretary of State of Health together with the Secretary of State of Business, Innovation, and Skills jointly asked HEFA to form this task force, a necessary first step to bringing this potentially life-saving technique to clinical trials. The public dialogue will begin later this year and be guided and overseen by a panel of experts. Additionally, the biomedical charity Welcome Trust has promised funds for preclinical safety experiments and the Nutffield Council on Bioethics has started an independent review. Here seems to be a perfect case where scientists, government, and policy experts are working together instead of just talking past or at each other.
There are two procedures currently under development: pronuclear transfer and maternal spindle transfer. In the first an egg with mutated mtDNA is fertilized in vitro, then the resulting pronucelus is removed and transferred to a donor egg that has had its pronucleus removed. The second technique involves chromosomes (DNA) taken from an unfertilized egg with mutated mtDNA being added to an unfertilized donor egg lacking a nucleus, then fertilization occurs in vitro. Pronuclear transfer has been successfully preformed on defective human eggs and maternal spindle transfer has been used to produce two healthy rhesus monkeys. Additionally, HEFA released a review in early 2011 finding the techniques not unsafe, although they did determine numerous additional studies would be required prior to beginning clinical trials.
These proposed IVF techniques, techniques that would produce children with three genetic parents, raise many important legal and ethical questions and issues. In the US federal funds cannot be used for research involving human embryos. Additionally, these procedures were banned by the British government in 2008 for safety, ethical, and research related reasons. But importantly, legislation was also put in place for a streamlined mechanism to legalize the techniques should scientific advances be made. Now, based on recent technical advances the British government has decided to take another look at the legislative ban. Chair of HFEA, Lisa Jardine, said in a recent press release, “This is an issue of great importance to families affected by mitochondria disease and it is also one of enormous public interest. The decision about whether this research technique should be made available to treat patients is one for the Secretary of State and, ultimately, Parliament. We will work hard to stimulate a rich and varied public debate, to help him make an informed decision.”