One has lost count of the stem-cell "breakthroughs" reported over the last decade. Some have turned out to be fraudulent, and all of them incapable of delivering any medical benefit. We should always bear in mind that the earliest report of stem cells, on the front page of the New York, claimed that stem cells were "immortal." We were therefore led to suppose that stem cells would deliver us from the perils of aging. Those claims have long since been abandoned, but the hype persisted in other forms -- stem cells could be used to treat Alzheimer's, for example, or diabetes, or Parkinson's disease.

The latest breakthrough, reported last week by Science and Cell, has been called "direct reprogramming." The claim is that with the addition of a mere four genes, an ordinary skin cell can be transformed into a pluripotent cell capable of achieving any desired specialization. (It is said that there are 220 types of cell but that number keeps changing and is a guess.)

The point about the latest claim is that it involves no recourse to egg or embryo. According to the hype, we can now directly convert cells of one type into any other type by this new method.

If so, this is all to the good, because if the claims are true the medical benefits of stem cell manipulation will be achievable without having to create or destroy embryos.

It is predictable, however, that nothing will come of the latest claims.

If you examine the fine print, you find that the new, allegedly pluripotent creations are by no means the same as embryonic stem cells. According to Dr. M. William Lensch, a senior scientist in the stem cell program of Harvard's Children's Hospital in Boston, they are "actually not identical." He said:

"For example, one paper showed that a few thousand genes (of more than 32,000 analyzed) in the skin based stem cells were not activated to the same degree that they are in embryonic stem cells."

Oh. So they differ in only a "few thousand genes." Yet Gina Kolata had reported in the New York Times that the addition of four genes to skin cells turned them into "what appear to be embryonic stem cells."

Nonetheless, I welcome the latest claim. It seems to me that it is ethically uncontroversial and it will therefore allow us to focus without distraction on the science alone (as I did in my Politically Incorrect Guide to Science.) Remember this: After ten years, researchers have not been able to achieve any of the medical promises, despite efforts in biotech labs all over the world, and in countries (such as Britain, Japan, Korea, Israel, Singapore and others) where the research was not only unrestricted but government subsidized. And despite the U.S. restrictions, research has continued here, too, with private money or with taxes from a handful of states.

A friend of mine who runs a small biotech company in San Francisco and has type 1 diabetes has closely monitored stem cell research, because in juvenile diabetics the disease wipes out the insulin producing beta cells of the pancreas. It is life-threatening condition, even if tractable with insulin injections. But it also focuses the mind, and he does pay close attention. He tells me that no stem cell work anywhere has yet been able to generate a single insulin-producing cell, and he doesn't believe the new method will, either.

My guess it will take about three years before researchers decide that the new "direct reprogramming" technique is not working after all. By that time the labs engaged in this work will have been flooded with government subsidies. In my view, this has all along been a principal goal of stem cell researchers. Science is a high risk enterprise, but once you are on the government payroll it becomes a Monday-to-Friday, nine-to-five routine. It's so much more comfortable that way.