UK’s approval of mitochondrial donation shows how decisions on gene editing can be made

BMJ 2015; 351 doi: (Published 10 December 2015) Cite this as: BMJ 2015;351:h6745
  1. Nigel Hawkes
  1. 1London

The approval in the United Kingdom of mitochondrial donation provides a blueprint for future decisions on modifying the genome, the government’s chief scientific adviser told a conference in London on Wednesday 9 December.

Mark Walport said that the UK should be proud of the process through which mitochondrial donation was approved, culminating in votes in parliament earlier this year and regulations that came into force on 29 October.1 These made it possible for women with abnormalities in the mitochondrial DNA of their eggs to avoid giving birth to unhealthy children by replacing that DNA with donated material.

Several steps remain before the technique is actually used, the chair of the Human Fertilisation and Embryology Authority, Sally Chaplin, told the Progress Educational Trust’s annual conference. “Once final safety and efficacy tests are completed, we will be able to offer licences to clinics to carry out the procedure” she said.

Doug Turnbull, director of the Wellcome Trust’s Centre for Mitochondrial Research at Newcastle University, added that an appropriate patient pathway had to be developed, and the treatment needed to be commissioned by the NHS. The numbers of women seeking treatment were likely to be small, around 10 to 20 women a year from the UK, and treatment would be approved on a case by case basis. For some women there may be alternatives, such as preimplantation genetic diagnosis.

Chaplin said that the approval of mitochondrial donation had been a long process, starting more than a decade before the issue was put before parliament. If there was one thing she regretted it was the time it had taken. “It’s amazing how long this has been a topic of discussion, and it would have been good to have an answer sooner,” she said. “When we carried out our consultation on the issue, gene editing wasn’t even being talked about. But progress there has been really fast paced, so we need to get things in place very fast.”

She was referring to the next challenge to regulators and policy makers: how to deal with the new technique for gene editing, called CRISPR-Cas9. This makes it possible to modify genes more accurately than ever before, even those of gametes or embryos, in which case the changes would then be passed on to succeeding generations. An international summit meeting in Washington, DC last week gave cautious approval to research and did not rule out clinical use as science advanced and society’s views evolved.2

Walport said he thought that these conclusions were “very sensible,” adding that clinical applications of CRISPR-Cas9 were still a long way off and that a distinction existed between altering somatic and germline cells. “It’s silly to ask if gene editing is a good thing or not,” he said. “What matters is what part of the gene you are modifying, and for what purpose. We need to avoid confusing discussions about science with discussions about values—there’s a risk of conflating the two. Sometimes people conceal their real objectives by claiming there is something wrong with the science.”

He said that the UK and the rest of Europe often differed over such issues. “Different countries have different views, and I can understand that,” he said. He saw the solution in allowing greater subsidiarity, whereby decisions are left to individual nations, and he hoped that the debate over genetically modified food was moving in that direction. “There is no absolutely right answer to these questions, and I think we have to find ways of accommodating plurality. I don’t think we’ve done that yet.”

Robin Lovell-Badge of the Francis Crick Institute, who was one of the organisers of the meeting in Washington, DC, said that a similar debate had preceded every advance in reproductive technology. In the past it had been possible for scientists to say that gene editing techniques were too inefficient, but this was no longer true. The “extraordinarily powerful” technique of CRISPR-Cas9 was very specific, very accurate, and very versatile, he said. Off-target events were rare.

“Why do it?” he asked. “To understand human biology better, to study models of disease, to treat or prevent disease, or to improve human capabilities. We modify everything: our diet, our environment, our climate. Why not ourselves?”


Cite this as: BMJ 2015;351:h6745


View Abstract

Log in

Log in through your institution


* For online subscription