More on mitochondria

At the end of last year Nature Medicine listed a timeline of the top stories of 2012. Amongst them was the publication in June of the Council’s report on techniques for the prevention of mitochondrial DNA disorders.

I am now wondering whether by the end of the year Nature will be lining up another list, in which mitochondrial replacement appears once more, because the HFEA will later this week announce the outcome of their consultation on the techniques, a consultation that the Government asked them to carry out in order to inform consideration of whether to make the treatments lawful.

Unlike much of the media, Nature avoided use of the term ‘three-parent babies’. As Geoff Watts, who chaired our Working Group, said in his blog at the time, the three parent tag is unhelpful, and diverts attention from some rather more important and substantial issues. Those issues include whether mitochondrial replacement amounts to germline therapy; whether this would open the door to other germline treatments; whether mitochondrial replacement in any way affects identity; and how we think about the research and regulatory environment in which the procedure might advance.

The reason the Council carried out its study was to ensure that the ethical considerations were given a good airing before the HFEA consultation and public dialogue got underway, and to help inform that process. With the HFEA about to announce its findings, let us just remind ourselves of the Council’s conclusions. We said, basically, that:

• Mitochondrial replacement therapies would be an ethical option for affected families, provided they are shown to be sufficiently safe and effective, and families are given appropriate information and support;


• The treatments would constitute a form of germline therapy as the changes would be passed on the descendants of any girls born from these techniques;


• This would not open a gateway to other germline therapies (acting on the nuclear genome), as they would involve altogether different techniques, and would require fresh debate and legislative consideration;


• The parentage of the child would be unambiguous – whilst the donor does contribute 0.1% of the child’s DNA, this does not signal any notion of biological or legal parentage;


• The techniques would not have any particular implications for the identity of offspring as we found that no particular social or cultural significance is placed on mitochondrial inheritance; and


• If offered, the techniques should be conducted within a licensed, closely regulated environment, by specialist centres in the context of research that would include long-term follow-up.

It will be interesting to see on Wednesday the outcome of the HFEA’s consultation and wider dialogue, and whether it chimes with the position that the Council arrived at.

But it will also be very interesting to see whether the media can resist the temptation to once again divert attention, unhelpfully and unnecessarily, by their mistaken notion of triple parentage. Geoff was not confident that they could resist when he wrote his blog nine months ago. I am not much more confident now, despite the good example of Nature Medicine.