April 18, 2019

expert reaction to media reports that a US scientist has used mitochondrial replacement therapy to make embryos for four women who are carriers of mitochondrial disease

Expert reaction to media reports that a US scientist talking at a public meeting at Harvard University has said he has used mitochondrial replacement therapy to make embryos for four women who are carriers of mitochondrial disease, and that the embryos are now frozen as US law prohibits him from transferring them into a womb.

James Lawford Davies, Partner at Hill Dickinson LLP, said:

“The UK is fortunate to have a mature, comprehensive legal framework which governs the clinical use of mitochondrial transfer and related research.  This allows suitably qualified experts to apply for a licence from the HFEA to allow them to treat patients who have a high risk of passing on a serious mitochondrial disease to their children.  It took many years of research, consultation and debate for the treatment to become lawful in the UK – all of which can now help inform the debate in the US, and hopefully lead to change in policy, allowing families affected by these cruel diseases to have healthy children.”

Prof Robin Lovell-Badge, Group Leader, The Francis Crick Institute, said:

“The US does not really have a Federal regulatory system governing assisted conception and related techniques, but anything involving the introduction or exchange of DNA into or between early human embryos would fall under the remit of the FDA and would have to be approved by them.  However, while a US National Academies of Medicine Report on Mitochondrial Replacement was reaching its conclusions (which were published in February 2016), a rider added to an appropriations bill towards the end of 2015 made it illegal for the FDA to receive any applications to do this.  This rather took the steam out of the conclusions of the NAM Report, which were reasonably positive that the methods of mitochondrial replacement could be allowed to avoid children having serious mitochondrial disease.

“Similar conclusions had been reached in the UK, but these had already gained both public and political approval.  The UK, with its very different approach to regulations in this area, involving the HFEA, has permitted the use of mitochondrial replacement since February 2015 (although a cautious approach meant that it took a while to establish the precise conditions under which the techniques could be applied).  It is a pity that the US does not have a similar, more appropriate regulatory system, where a distinction can be made between mitochondrial replacement and germline genome editing, and where the use of methods for specific purposes involving a justifiable clinical need can be permitted, while other uses where suggested benefits may not outweigh the risks, would not be allowed.  Thus, in the UK, mitochondrial replacement can be used to avoid severe mitochondrial disease, but not to treat female infertility.

“As other countries, notably Australia and Singapore, consider changing their laws in line with the UK on this, it is appropriate that the US does so as well.  While it must be very frustrating for the parents to have to store frozen embryos after mitochondrial replacement, it is better to change the laws to permit their use to derive babies, than to export them to a country that lacks regulations.”

Declared interests

Prof Robin Lovell-Badge: “Robin Lovell-Badge was a member of the HFEA’s Panel that conducted reviews of the scientific methods to avoid mitochondrial disease from 2011 to 2016.”

None others received.