I have posted many times on the hype surrounding embryonic stem cell research, and how this hype has bordered on being on par with the snake oil salesman of the past. Now one of the founders of the stem cell concept has come forward to take on the inaccurate and pollyannish propaganda about stem cell research.

A leading scientist who pushed for the controversial research into embryo stem cells will warn today that the challenges are so huge that any cures for disease lie a long way in the future.
Lord Winston, who pioneered fertility research in the UK, is to tell the British Association for the Advancement of Science, meeting in Dublin, that during the political campaign to push through legislation in 2001, some parliamentarians were led to believe that clinical treatments were “just around the corner”. Some of the lobbying came from patients’ groups, but it was stimulated by scientific observations.
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He singles out embryo stem cells as a case study in scientific arrogance and the dangers of “spinning” a good story.
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Leading US scientists have come to the UK to join what Lord Winston calls “one of the most exciting areas in biology”. But, he says, embryonic stem cells may not be useful for a long time.

“I view the current wave of optimism about embryonic stem cells with growing suspicion. Embryonic stem cells replicate very slowly in culture, and it may well be that in the culture systems where you want to grow them the selective pressure is in favour of the faster growing cells, the ones of course which are most likely to be genetically abnormal,” he said.

This is why the adult stem cells, partially differentiated to a class of cells but still able to go through a final transformation step to a large variety of important cells, will probably result in therapies quicker than the embryonic research. Winston identifies a lot of under-reported challenges associated with embryonic research:

Embryos showed a remarkable propensity to produce abnormal chromosomes, he said. Stem cells that had differentiated into one kind of tissue had been seen to change back again. If these were transplanted to a patient, they might cause harm.
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In fact the natural life cycles of stem cells – 48 hours, or even 72 hours – posed huge problems. Lord Winston said that that length of time might mean the disease overtaking the patient. “That replication also means there will be faster growing cells in the same culture that will probably swamp the slower growing cells. And those cells that are growing faster are almost certainly not expressing genes in the ‘normal’ way.

Winston appears to backpedal in the end, possibly hoping his candor will not cause a loss of support to his cause:

“So I think there is a problem selecting the right cells. I think we are quite properly concerned with increasing caution – but [that] does imply we may have oversold this subject a bit too much.”

In one sense Winston is probably correct. He and some other cautious scientists may not have over sold the promise of embryonic stem cell research – but many others have. The fact these problems well known to people with a scientific background are not widely known in the public is prima facia evidence embryonic research has been oversold.