How scientists won the 3-parent IVF battle

Michael Cook
7 February 2015
Reproduced with Permission

After years of debate, the British House of Commons approved the creation of embryos with genetic material from two women and one man by a vote of 382 to 128. The House of Lords will probably pass the bill, which amends the 2008 Human Fertilisation and Embryology Act, later this year.

Prof Alison Murdoch, one of the technique's pioneers, said: "This is good news for progressive medicine. In a challenging moral field, it has taken scientific advances into the clinic to meet a great clinical need and Britain has showed the world how it should be done."

How was it done? How did British scientists manage to persuade Parliament to overcome the "moral challenges" and to accept "progressive medicine"? Its opponents had described mitochondrial transfer ominously as genetic engineering, three-parent babies, and eugenics. Why didn't Parliament buy it? There are lessons here for other countries where this technique will be debated in the not-too-distant future, like the US and Australia.

The technique is so controversial that even its name is a matter of dispute. Supporters describe it as "mitochondrial transfer"; opponents and the media call it "three-parent embyros". There are two approaches, one beginning with a woman's eggs and the other with an embryo. But both transfer the nucleus of a cell with faulty mitochondria floating in its cytoplasm into a cell with healthy mitochondria from a second woman.

There appear to be seven strands in their lobbying strategy.

Advance planning: a number of scientific, ethical and public consultations have been carried out since 2011, with the enthusiastic backing of well-funded scientific and government organisations. Their patient work to win over the politicians and the media was rewarded.

Exaggerate the health impact of the technique. The technique is meant to help families whose children would otherwise live with a mitochondrial disease. These vary greatly in severity, but at their worst the children suffer from diseased organs, gastrointestinal disorders, respiratory disorders, neurological problems, autonomic dysfunction and dementia. There are various estimates of how many families would be helped by the IVF technique. Nature News said that 2,000 women "could benefit", based on a data from a recent letter in the New England Journal of Medicine . However, the letter actually said that only 152 women would be "at risk" each year. Of these, perhaps 10 or 20 might take advantage of the technique. If Parliament were really interested in curing children, why not back research into Ebola? That has killed thousands of children.

Highlighting the suffering of the children and their parents. Some affected families have had very tragic experiences. One woman, Sharon Bernardi , lost all seven of her children. But there are many families with children who suffer painful diseases whose stories never appear in the media. Those affected by mitochondrial disease are different because their stories were amplified by a powerful public relations machine.

Framing the technique as a cure. In the media, mitochondrial transfer was consistently described as a cure for dread diseases. In fact, not one child will be cured; instead, healthy IVF children will be created. The editor of the Journal of Medical Ethics , Julian Savulescu, phrased this point very carefully in an article for the Guardian : "Importantly, by doing this transplant at the very early stage of embryo development, the disease is cured [my italics ]. The children of the offspring of this procedure will themselves be free of mitochondrial disease. It would be eradicated forever in this family." But in a video directed at members of Parliament, he said, less cautiously, "every year 150 children are born with this condition and you have the power to cure them ." This is not true.

Redefining the human person as nuclear DNA. Mitochondrial DNA constitutes only 0.054 per cent of the total DNA in a cell, according to Dame Sally Davies, Chief Medical Officer for England , who played an important role in the debate. It is the DNA in the nucleus "which determines our personal characteristics and traits such as personality, hair and eye colour". This was repeated over and over by supportive scientists: mitochondrial DNA is just a battery pack. No one explained how mitochondrial DNA could be both a negligible part of the human person and also have such devastating effect upon a child's organs, systems and personality.

Redefining genetic engineering. Genetic engineering is modification of the genome; scientists redefined it as modification of nuclear DNA. The mitochondrial DNA is simply a replaceable module or an interchangeable spare part. In one of the cleverest redefinitions, Stephen Wilkinson, a bioethicist at Lancaster University, wrote that "mitochondrial replacement isn't genetic modification as such, but rather donation … nothing really new is being added to the human gene pool." In other words, genetic engineering only happens if an artificial or non-human gene is added to an embryo.

Moving the goal posts like this is an old debating trick. Vladimir Putin used it when Russia absorbed Crimea. We are fully, fully, committed to the territorial integrity of Ukraine. What about that illegal invasion of Crimea stuff then? Illegal? You don't understand; Crimea has always been part of Russia, my friend. We are fully, fully, committed, etc.

Exaggerating the extent of their knowledge. Not all scientists welcomed the decision. Paul Knoepfler , of UC Davis School of Medicine, and a leading American stem cell researcher, thought that legalisation was premature:

"There is no doubt that mitochondrial diseases are truly terrible and need to be addressed, but if the potential outcomes from the technology are still vague, there are safety concerns, and it raises profound ethical issues such as changing the human genome heritably as is the case here, then my view is that a careful approach is both practical and logical. We cannot at this time have a reasonable expectation that this technology would be safe and effective. That may change in coming years with new knowledge. I hope so.

"As strange as it may sound, although mitochondria have been studied for around 150 years, they remain in many ways still a new frontier for science with many mysteries. We are only now, for example, starting to understand how the mitochondrial genome works. There was just recently a very unexpected discovery that the mitochondrial genome produces thousands of potentially powerful non-coding RNAs with largely unknown functions. Nobody has any clue how these RNAs might behave in the context of mitochondrial transfer."