Bioethics council report on techniques to treat mitochondrial diseases

Posted on June 14, 2012 by


This week the Nuffield Council of Bioethics launched the conclusion of its six-month review into the ethics of novel techniques to prevent mitochondrial disease. Few treatments exist and the research underway involves new science which changes the germ line of cells so it’s highly controversial. The conclusions of the Nuffield report and the HFEA consultation into public attitudes to this area will help inform the Government’s decision on how to regulated these emerging treatments.

First a bit of background

Mitochondria are tiny structures found inside cells that provide the energy for cells to function. They are small but very interesting because they contain their own DNA containing 37 genes. Crucially, these are only transmitted down the maternal line so a mother with defective mitochondrial genes will pass them to her child. Because mitochondria are vital to provide energy, those cells that have the most need of energy (brain, heart, muscle) are the most affected when mitochondria go wrong – and it is for this reason that the symptoms of mitochondrial diseases can be so varied and severe and affect so many of the body’s functions. You can find some of our earlier discussion of the science on our previous posts here.

It’s a controversial area because the science is new and the ethics are challenging. Techniques to tackle mitochondrial disease create embryos with a nucleus with the genes of both mother and father and then transplant that nucleus into a donor egg which contains mitochondria (and so a tiny amount of DNA) from a third person. This is why the papers (somewhat unhelpfully) are referring to the techniques as three parent IVF.

Several research projects are currently underway to explore the possibilities of these techniques and to better understand their safety and effectiveness. Their use in treatment is currently forbidden by law – “eggs, sperm or embryos which have had alterations made to their nuclear or mitochondrial DNA may not be placed in a woman’s body”.

What does the Nuffield report say?

You can read the executive summary here. The report sets out several key conclusions:

  • Important ethical implications for identity and parentage. The Working Group recognised that though any resulting child would have a genetic contribution from a third party but mitochondrial donation would not imply a third parent on either biological or legal grounds
  • These sorts of techniques do constitute germ line modifications, meaning the genetic alteration will be passed on to future generations, and so need to be considered in that light from a regulatory and ethical standpoint
  • It is vital to properly assess the risk of such techniques if they were to become viable clinical treatments with detailed long term follow up and proper regulation
  • And the status of the mitochondrial donor in regulation is not equivalent to the status of either egg or embryo donor and so would not be identifiable in law as other donors currently are.

What has been the AMRC position so far?

We wrote on behalf of members to Andrew Lansley, the Secretary of State for Health, in April 2011 to encourage the Government to move quickly to develop regulations to license mitochondrial replacement techniques. And we submitted a joint response with one of our members, Muscular Dystrophy Campaign, to the Nuffield Consultation setting out our belief that once proven sufficiently safe, the translation of these techniques into clinical use could have the potential to help thousands of couples in the UK who currently risk passing inheritable mitochondrial disorders, and for whom there is no cure.

What next? It’s in the Secretary of State’s hands

Andrew Lansley has asked an expert panel convened by the HFEA, the body that regulates such techniques for research and treatment, to launch a public dialogue project on the ethical and regulatory issues involved in order to understand:

  • how (and what) people currently comprehend the ethical issues associated with mitochondirnal transfer
  • the difference between informed and uninformed views
  • the regulatory and ethical issues involved in licensing mitochondrial transfer

I am sitting on that panel and we have already begun some initial survey work to kick that process off. The main consultation will launch in September 2012 (more information here). It is a fantastically important project both to explain complicated science to the public and to seek their views on the ethical issues involved.

Ultimately, of course, the decision about whether or not this research technique will be made available to patients is for the Secretary of State. But the chance to stimulate a rich public debate, to move the dialogue from notions of frakenbunny and slippery slopes to a thoughtful and insightful discussion on the issues, benefits and risks, will be an important element in helping Parliament to make an informed decision about techniques that could yield an answer for some dreadful and currently incurable diseases.

Posted in: Policy, Research