Is the unstoppable advance of therapeutic cloning in danger of grinding slowly to a halt? This week a bill authorizing it in Western Australia failed on a conscience vote in the upper house by a vote of 18 to 15, even though similar acts had been passed in Canberra and in NSW, Victoria, Tasmania, Queensland and the ACT. It could signal a major setback for supporters of destructive embryo research.

Significantly, this may have been the first time that the issue has been thoroughly debated in any legislature since the startling discovery of an ethical way of obtaining pluripotent stem cells. It could mean that legislators elsewhere may balk at passing laws which authorise therapeutic cloning.

Since Japanese researcher Shinya Yamanaka published a landmark paper in November showing that it was possible to make ordinary skin cells revert to an embryonic state, the scientific landscape has changed rapidly. These new cells, called induced pluripotent stem cells, are still being investigated, but they appear to be far easier to work with than embryonic stem cells. And like them, they can apparently develop into any cell in the body. They may even be better than cells derived from cloning because they are a 100% match for the patient, unlike cloned cells which contain mitochondrial DNA from a woman´s egg.

Therapeutic cloning also requires an abundant supply of eggs. This could lead to the exploitation of women, a possibility which cast another shadow over the bill for WA MLCs. This is one more ethical problem which iPS cells avoid.

WA Health Minister Jim McGinty, a strong supporter of the legislation, was bitterly disappointed by the defeat. He says that an avenue for cures for spinal cord injury, dementia, Alzheimer´s and Parkinson´s disease and many cancers had been blocked. However, Dr David van Gend, of Australians for Ethical Stem Cell Research, had a different view. "What the WA vote has shown is that MPs who are not trained scientists are nevertheless able to keep up with rapid changes in science, and when the facts change, they are able to change their minds," he commented. "There is no longer any compelling argument for cloning, and this blighted science can be left to wither on the vine."