Mitochondria donation nonsense

A bunch of mitochondria just hanging out.

For various largely uninteresting reasons, I’ve not blogged lately. But then I came across this article on The Guardian website today, a for-and-against piece about mitochondria donation with an “against” argument from Peter Saunders that veers from irrelevant to flat out wrong. Let’s get started!

To begin with, this is not about finding a cure. It is about preventing people with mitrochondrial disease being born. These new technologies, even if they work, will do nothing for the thousands of people already suffering from these diseases, or for those who will be born with it in the future.

Now, here’s the first dodgy argument, one that I’m almost tempted to call a dog-whistle. Mitochondrial donations are not about “preventing people with mitrochondrial disease being born“, they’re about “preventing people being born with mitrochondrial disease”. Just look at how moving that phrase “being born” a few words to the right changed a factual statement about the procedure into a non-sequitur about abortion.

It’s of course true that unfortunately, this procedure will do nothing to help people that already have mitochondrial diseases – removing a mutation from the body is perhaps the most impossible thing in all of medicine – but that’s no argument against the procedure.

Also, Saunders claims that there is no need for the procedure when egg donation is already possible. Bear this in mind; it’ll come up again later.

Will it work? 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”). […] Yet cybrids are now a farcical footnote in history. They have not worked. Ironically, it was in that same act of parliament that provision for this new research was also made.

First of all, cybrids were legalised in 2008. 3-4 years is not that long a time in medical research, especially for research into slow-developing, long-term conditions like Alzheimers and Parkinsons. But I decided to have a look on Google Scholar, to see if cybrids were just a “farcical footnote”. Since 2008, there have been at least 362 papers about cytoplasmic hybrids, including 114 in the last year and a half or so. Some of these are papers exploring the ethics of the procedure, but an awful lot are detailing actual breakthroughs made using these cytoplasmic hybrids.

Embryonic stem cell research, being far more mature, is even more successful, with stem cells relieving paralysis in rats and the first clinical trials in humans showing promising results. Hardly a field that has “thus far failed to deliver”.

But even if he was telling the truth, and both fields had proved to be dead ends, this would still be irrelevant to mitochondrial donation. All it says is that mitochondrial donation uses one technique which is also used in stem cell research. As far as arguments go, this is up there with “vegetarians are evil because Hitler was a vegetarian”.

Is it safe? No. Each technique involves experimental reproductive cloning techniques and germline genetic engineering (that is, it affects the genes passed on to children) – both of which are highly controversial and potentially 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 others suffering from physical abnormalities or limited lifespans.

Well, it’s good thing there’s no cloning involved with this technique, thus making that last sentence completely pointless scaremongering.

Also, as the Guardian noted last week, any changes, or unpredicted genetic problems (mutations) will be passed to future generations.

This is true, but the thing is: if a woman with a mitochondrial condition doesn’t use this technique and conceives a child naturally, there is a 100% guarantee that the mitochondrial defect will be passed to the future generation(s). The whole point of this method is to reduce the number of dangerous mutations being passed on.

Is it ethical? No. A large number of eggs will be needed, involving risky and invasive “harvesting” for women donors. How many debt-laden students or infertile women will be exploited by the offer of money, or free IVF treatment, in return for their eggs? How many embryos will be destroyed?

Ok, so, remember how earlier egg donation was a totally ethical alternative to mitochondrial donation? Well, with a deft sleight of hand Saunders is now claiming that egg donation is unethical!

There are concerns about paying people to donate body parts/fluids – it’s one of the most hotly discussed areas of bioethics – but in the UK, donors are not paid to donate eggs. They can have their travel and accommodation expenses paid (up to £750), but that’s it. There’s simply no room for the kind of exploitation Saunders worries about.

As far as I can tell, there is no difference to the egg donor between standard donation and mitochondria donation. The technique doesn’t necessarily require any extra eggs – though I suppose that depends on its success rate, which, since the technique is still experimental, no-one yet knows – and it doesn’t require any more embryo destruction that IVF or standard egg donation.

Then there are the issues of identity confusion for the children, who in effect will have three biological parents. 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?

The mitochondria are, as the standard explanation goes, the little power stations that fuel each cell, and mitochondrial DNA has no effect on the wider body outside these power stations. A baby conceived by mitochondria donation is closer to having two parents than than a baby conceived by standard egg donation (since in mitochondria donation, all the DNA that affects what the baby actually looks like comes from the mother, not the donor), and if “identity confusion” is a concern, it’s odd that he’d endorse adoption either. And this technique does not mean any baby is “not worthy of being conceived” (unless he’s referring to the parents’ choice not to conceive naturally in the first place, in which case his argument is grosser and more unethical than I thought) – conception will still happen, it’s just that egg will be slightly modified first.

This debate is not being handled responsibly. The research scientists involved have 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.

I don’t think “I’m a research scientist and I want to continue my research” counts as a vested interest. It’s not like researchers are pretending their research isn’t dependent on this technique being allowed. I genuinely wonder how Saunders would prefer this debate be handled – he certainly never explains. Speaking of not handling debates responsibly, though neither Saunders nor The Guardian point this out, Saunders is the CEO of the Christian Medical Fellowship, a group that speaks out against a variety of medical techniques on religious grounds. As Mark Henderson said on Twitter, “Saunders makes many bad arguments vs mitochondrial transplants, omitting real reason he opposes: religion […] Nothing wrong with opposing embryo research for religious reasons, but those who do should admit it, and that no evidence would convince them”

Let’s concentrate on finding treatments and providing better support for affected individuals, rather than spending limited health resources on unethical, risky and highly uncertain hi-tech solutions that will most likely never deliver.

We already know that, no matter how difficult mitochondrial donation is, finding a cure for mitochondrial disorders is far far harder still – and perhaps impossible with our current knowledge of genetics. A human body contains billions of cells, each one containing at least one and often tens or hundreds of mitochondria. Replacing or fixing all of them would be far more difficult than replacing the mitochondria in a single cell; if you want an efficient way of spending limited health resources (really, limited research resources – the funding for this research would not be directly linked to the NHS), donation research is surely a better route to take.

(I intended to, for balance reasons, point out any inaccuracies in the response from the Nuffield bioethicist arguing for the procedure, but it already seems pretty sensible and fair. Quelle surprise…)

Edit: Also thanks to Mark Henderson for pointing out that the research is being carried out at Newcastle University and entirely publicly funded by the Wellcome Trust and the Medical Research Council – there are no vested business interests involved either.

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