Friday 11 March 2011

More hype about three-parent embryos – don’t hold your breath about the promises of new therapies

Health Secretary Andrew Lansley has asked the Human Fertilisation and Embryology Authority to assess a controversial fertility treatment.

The ‘three-parent IVF’ technique developed at Newcastle University (on which I commented last April) involves creating a fertilized egg in a laboratory, then removing its nucleus and placing it into another embryo from which the nucleus has been removed (see picture above).

The resulting embryo has nuclear DNA from a man and a woman and cytoplasmic DNA from a second woman - so effectively three genetic parents, although the contribution from the second woman is very small.

Researchers claim the technique could help prevent mothers passing on a rare inherited condition called mitochondrial disease to their children. Mitochondrial disease is unusual in that it is transmitted through DNA in the mitochondria (cell 'batteries') in the cell cytoplasm rather than through DNA in the cell nucleus.

Although they admit that they are far from ready to use the technique on patients, they feel that because the science is progressing ‘very rapidly’, the review of the process, which would inform political debate, needs to start now.

Getting the regulatory changes necessary to allow using the technique in patients now no longer involves parliament but only approval from the Health minister. The HFEA panel is set to submit its report to the government next month.

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

We need to be clear in the first instance that this new ‘treatment’, even it were eventually to be shown to work (and there is considerable doubt about that), 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.

It is primarily about trying to prevent people with MCD being born - or at least helping a very small number of mothers who carry the gene to have children who are unaffected.

And we need to remind ourselves that there are already some solutions available for those couples who find themselves in the tragic position of carrying genes for mitochondrial disease – including adoption and egg donation (although I have serious ethical reservations about the latter)

But I have three big questions about this new technique:

1.Will it work? I am very skeptical!
2.Is it ethical? No, there are huge ethical issues!
3.Is the debate being handled responsibly? No, there are huge vested interests involved!

I have a great sense of déjà vu here. There is always in this country huge media hype about supposed breakthroughs in biotechnology and the IVF industry – especially the Newcastle group - is very skilled in arousing media interest.

But we have been here before with human reproductive cloning (the Korean debacle), so-called therapeutic cloning for embryonic stem cell research (which has thus far failed to deliver) and animal hybrids (now a farcical footnote in history)

We saw the false dawn most clearly with animal human hybrids where the biotechnology industry, scientists, patient interest groups and science journalists on the UK nationals duped both the public and parliament into legalising and licensing animal human hybrid research to produce stem cells.

But even before the ink was dry on the 2008 HFE Act researchers and investors were recognising that the technology who almost certainly not deliver – that there where more effective ethical alternatives available (such as induced pluripotent stem cells or IPs)

The Newcastle unit is a world leader in promising much and delivering little – but given the short attention span of the media and the gullibility of the public few people seem to realise, remember or care.

The UK broadsheets this morning largely transcribe uncritically the spin of the Newcastle unit’s press release – whilst giving scant attention to the questions of safety, efficacy and ethics being raised by commentators in scientific journals and blogs. Some questions that you will not hear asked or answered:

1. What will be the effect on the embryos of the small amount of abnormal cytoplasm containing defective mitochondria that is still being transferred?
2. Will any of these embryos survive beyond blastocyst stage? (cloned human embryos and animal-human hybrids produced by similar ‘nuclear replacement’ technology haven’t)
3. If they do survive will the nucleus from one embryo function properly with the cytoplasm of another?
4. Will the progeny be normal or be suffering from defects that are in fact worse than mitochondrial disease itself? (we know that cloning by nuclear replacement is possible in frogs, difficult in mammals, hugely problematic in non-human primates and currently not possible in humans)
5. What about the hundreds of embryos that have already been destroyed in the research?
6. What will be the psychological effect on any progeny of the fact that their DNA is derived from three separate ‘parents’?
7. What will be the effect of the introduced transmissible DNA on future generations?

We also need to realise that the Newcastle scientists have a huge financial and research-based vested interests that make it very difficult for them to be balanced and objective in the way they present their findings.

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. And they know that that is best achieved through attention-grabbing media headlines and press releases and heart grabbing (but highly extreme and unusual) human interest stories that are selective about the truth.

What is currently happening in Newcastle may be legal in Britain – but it is illegal in almost every other Western country for good public safety and ethical reasons. Britain is regarded by many as a rogue state in all this.

So I’m not letting myself be carried away by the hype and spin. And I’m not holding my breath about the promises of therapies.

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