Three parent embryos for mitochondrial disease – unsafe, unethical and unnecessary

Britain is planning to become the first country in the world to offer controversial ‘three-parent’ fertility treatments to families who want to avoid passing on mitochondrial diseases to their children.

The BBC reports this morning on the new techniques which it is claimed will children born through 'three-person IVF' who would carry genetic material from each of three different people.

There are about 50 known mitochondrial diseases (MCDs), which are passed on in genes coded by mitochondrial (as opposed to nuclear) DNA. They range hugely in severity, but for most there is presently no cure and little other than supportive treatment.

It is therefore understandable that scientists and affected families want research into these two related ‘three-parent embryo’ techniques (pronuclear transfer and maternal spindle transfer) to go ahead. But there are good reasons for caution.

This is not about finding a cure. It is about preventing people with MCD being born. We need first to be clear that these new technologies, even if they are eventually shown to work, will do nothing for the thousands of people already suffering from mitochondrial disease or for those who will be born with it in the future.

There are also already some alternative solutions available for affected couples including adoption and egg donation.

But apart from this I’m left with four big questions.

Is it safe? This is far from established. Each technique involves experimental reproductive cloning techniques and germline genetic engineering, both highly controversial and potentially very dangerous. Cloning by nuclear transfer has so far proved ineffective in humans and unsafe in other mammals with a large number of cloned individuals spontaneously aborting and many others suffering from physical abnormalities or limited lifespans. Also, any changes, or unpredicted genetic problems (mutations) will be passed to future generations. In general, the more manipulation needed, the higher the severity and frequency of problems in resulting embryos and fetuses.

Will it work? I am sceptical. This technology uses similar ‘nuclear transfer’ techniques to those used in ‘therapeutic cloning’ for embryonic stem cells (which has thus far failed to deliver) and animal-human cytoplasmic hybrids (‘cybrids’). The wild claims made about the therapeutic properties of ‘cybrids’ by the biotechnology industry, research scientists, patient interest groups and science journalists duped parliament into legalising and licensing animal human hybrid research in 2008. Few now will remember Gordon Brown’s empty promises in the Guardian on 18 May that year of ‘cybrids’ offering 'a profound opportunity to save and transform millions of lives' and his commitment to this research as 'an inherently moral endeavour that can save and improve the lives of thousands and over time millions of people'. That measure was supported in a heavily whipped vote as part of the Human Fertilisation and Embryology Bill, now the HFE Act. But ‘cybrids’ are now a farcical footnote in history. They have not worked and investors have voted with their feet. Ironically, it was in that same Act of Parliament, that provision for this new research was also made.

Is it ethical? No, there are huge ethical issues. A large number of human eggs will be needed for the research, involving ‘harvesting’ that is both risky and invasive for women donors. How many debt-laden students or desperate infertile women will be exploited and incentivised by being offered money or free IVF treatment in return for their eggs? How many thousands of human embryos will be destroyed? If it ever works, what issues of identity confusion will arise in children with effectively three biological parents? What does preventing those with mitochondrial disease being born say about how we value people already living with the condition? Where will this selection end? Some mitochondrial diseases are much less serious than others. Once we have judged some affected babies not worthy of being conceived, where do we draw the line, and who should draw it?

Is the debate being handled responsibly? No. The research scientists involved have huge financial and research-based vested interests and getting the regulatory changes and research grants to continue and extend their work is dependent on them being able to sell their case to funders, the public and decision-makers. Hence their desire for attention-grabbing media headlines and heart rending (but highly extreme and unusual) human interest stories that are often selective about what facts they present.

It must be tempting for politicians to make promises of ‘miracle cures’ in years to come which no one may remember. But I suspect it is much more about media hype than real hope.

This new push is being driven as much by prestige for government, research grants for scientists and profits for biotechnology company shareholders as anything else.

Let’s keep a cool head and instead concentrate on finding real treatments and providing better support for affected individuals and their families rather than spending limited health resources on unethical, risky and highly uncertain high tech solutions that will most likely never deliver. 

 (See BBC, Guardian, Times(£), Independent, Daily Mail and Telegraph).