http://www.abc.net.au/catalyst/stories/2608076.htm
Last night we saw that rarest thing: a nearly-accurate presentation of stem cell science on television. At last, the popular programmes – from Oprah in the US, to this more serious show, Catalyst, in Australia – are getting the message right (and maybe without even reading this Blog…):
"You are about to witness what the Science journal described as 'breakthrough of the year'. Where stem cells are created from ordinary adult cells, without the use of eggs or embryos."
There is first a detour through the history of ESCs – where they politely avoid the issue of tumour formation, but do refer to the immune-rejection problem - and then a reference to ASCs – where the weary old fallacy shows up (that lacking pluripotency is a disadvantage of ASC – whereas, as we know, it is a curse to be pluripotent: it makes you a dangerous, tumour-forming nuisance). These supposedly less useful 'multipotent' ASCs are shown, in another segment of the show, being use as therapy for damaged cartilage – in both a horse and a patient. No tumours there! All good. See http://www.abc.net.au/catalyst/stories/2608197.htm Noticeable by their absence from any actual therapies are those little ESCs which are supposedly so much more 'potent'… Hey ho…
Next, the story returns to the Gee-Wizz headline about the iPS revolution:
"And in 2008, scientists did that successfully with human cells. They're called Induced Pluripotent Stem Cells, or iPS cells. Now in theory, any cell in our body can become like an embryonic stem cell. … Researchers are still figuring out how this amazing transformation takes place. Put simply you start with an adult cell, say a skin cell. You then insert four genes into the cell, the kind of genes responsible for regulating the cells development. And that effectively reprograms the cell, wipes the slate clean and sends it back to the embryonic state. You can then direct it to become any cell you like, say a heart cell."
Enter Prof Bob Williamson. This is the same scientist, spokesman for the AAS on cloning, who brought you the most offensive furphy in the early stages of the cloning debate – that cloning does not really create a human embryo (he called it an 'intermediate cellular product', as I recall). That argument was designed to remove the moral sting from cloning, since if it does not create a living human embryo, what is the big fuss? But eventually even Loane Skene of the Lockhart Committee admitted that – as with Dolly the sheep – SCNT cloning does indeed create a human embryo, which could, in theory, be born as a baby.
Interviewed for last night's show, the Professor appeared to be on song with the South Australian scientists who recently tried to denigrate iPS to MPs: try to smear iPS as being somehow uniquely 'dangerous', and therefore make the case (as in SA) that 'we still need to do cloning and ESC research…'
Here it is:
"But Bob Williamson urges we proceed with caution before injecting genetically modified IPS cells into people.
PROF. BOB WILLIAMSON:
"Obviously we have to know whether IPS cells can cause cancer or not and we don't even know that with certainty."
Cancer! Injecting cancer-causing cells into people! That gives iPS a real 'danger' label. Smart politics, but not a scientifically transparent statement of the equivalence, in terms of any 'dangers', of the new iPS and the old ESC. No, what a scientist in Prof Williamson's position might have explained to the viewer is this:
"Obviously we would never inject iPS cells into people any more than we would inject ESC into people. You can't do that, as they both form tumours. We can only inject ASCs into people. What we can do with ESC and iPS cells is study genetic disease and develop drugs against those diseases. And of course, dear viewer, any useful research an ESC could do an iPS can also do - because they are functionally identical cells. Indeed, the iPS is superior because it is an exact genetic match of the patient, while an ESC could only be a genetic match if one first clones the patient into an embryo, in order to destroy it for its stem cells… What sort of mug science is that, undertaking the ethically contentious, enormously expensive and technically difficult (indeed impossible, so far) act of SCNT cloning for stem cells, when you can so easily obtain the exact same research cells by scratching off a bit of skin?"
And then we have another worried comment from the Professor, this time on the troubling ethics (I jest not) of iPS: "the idea that every cell in your body has the potential to become an embryo, is itself a slightly scary thought". In the context of this TV story, his comment is another subliminal message of caution about these worrying little iPS cells - and it is a load of nonsense. There is only one cell in anyone's body that can 'become an embryo' and that is the oocyte. The woman's egg alone has the totipotency (that's one up on pluripotency) to 'become an embryo' once fertilised (or once tricked by cloning into 'thinking' it's been fertilised). Other cells can provide the nuclear DNA for SCNT cloning, and thereby act as a bogus 'sperm' - but they lack the cellular machinery for forming the whole show - placenta and embryo together. Prof Williamson is mistaken; no other cell in the body can ever develop into an embryo. Therefore his ethical suggestion that 'any cell' is now, since iPS, somehow morally equivalent to an embryo is misguided. It harkens back to his original attempt to degrade the true embryo created by cloning - to the status of an 'intermediate cellular product'; this time the moral equivalence smear is to upgrade 'any cell in our body' to the moral status of a potential embryo, and therefore remove the 'specialness' of the embryo.
Very disappointing spin coming from an honest scientist.
We can look forward to plenty more muddying of the waters by embryo-research advocates as we head into the cloning review next year. Yet shows like the ABC Catalyst of 25th June 2009 show that the truth of the redundancy of embryo experimentation is going to be harder to obscure behind scientific smokescreens.
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