Just Cloning Around

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PAUL J. RICHARDS/AFP

Michael D. West, Ph.D. and President & CEO of Advanced Cell Technology Inc.

Anyone who scanned the headlines last week might be excused for thinking a long-feared biological Rubicon had been crossed. Newspapers across the country, including the Wall Street Journal, USA Today, the Los Angeles Times, the Washington Post and the New York Times, put the story on the front page, and U.S. News & World Report splashed it on the cover, proclaiming THE FIRST HUMAN CLONE in big, bold type.

Pro-life politicians were quick to denounce the experiment. Kansas Senator Sam Brownback, a Republican, vowed to try to get the Senate to approve a bill before Christmas prohibiting human cloning. "The use of embryos to clone is wrong," declared President George Bush. "We should not as a society grow life to destroy it."

But a closer look at what researchers had actually done makes clear that nobody is anywhere near producing tiny carbon copies of human beings. Scientists at Advanced Cell Technology, a small Massachusetts biotech firm, only managed to grow "embryos" made up of a tiny handful of cells--and all those died almost immediately. Indeed, says George Seidel, embryologist at Colorado State University, "in terms of their objectives, it was a complete failure."

That may be too harsh. Just getting a human embryo started without the union of sperm and egg was a feat never before achieved. It's a step, though a small one, in a potentially important direction.

Still, by publishing the results at such an early stage--and, perhaps more important, by ballyhooing them in the popular press--the company may have shot itself in the foot. The blast of publicity may win ACT bragging rights and pull in much needed investment to fuel the company's research. But if the hoopla triggers a harsh anticloning backlash, it might dash whatever hopes ACT had of actually saving lives.

And that's really what this kind of cloning is about. "Our intention is not to clone human beings," insists ACT medical director Dr. Robert Lanza. Instead, the company's goal is

to make embryonic stem cells, the so-called starter cells that can turn into any sort of body tissue, from brain to bone to blood. In theory, stem cells might be used to treat any disease in which cell death is a factor: diabetes, Alzheimer's, Parkinson's disease, paralysis, stroke and more. And while stem cells can be harvested from aborted fetuses, that source is abhorrent to abortion foes--which is one reason President Bush declared last summer that only those stem-cell lines already in existence could be studied with government funds.

That ban doesn't affect ACT, which is privately funded, but stem cells from aborted fetuses are problematic in any case. Like any foreign tissue, they can trigger rejection; ideally, doctors would prefer to get stem cells from a patient's own body. The most direct way to do that is through cloning, and ACT scientists took the first steps in that direction by two different techniques. In one, they stimulated an unfertilized egg to begin dividing on its own. In the other, they removed the nucleus from a donated egg and inserted that of an adult--the same method used to produce Dolly the sheep, the world's first mammalian clone.

Though neither technique led to a viable embryo, company officials describe the experiment as a success. "No one has ever done this before in any primate," says Lanza. It's been done with plenty of other animals, but, he observes, "when you are working with cows or mice, you could easily be working with over 1,000 eggs; and we generated our results with only a handful of human eggs. That's pretty remarkable for a first attempt." Moreover, says Lanza, the potential of stem cells could be enormous. "We've already been able to turn animal stem cells into cartilage, skin, bone, beating heart cells and dopamine-producing neurons."

There are drawbacks, of course. To treat the tens of millions of people who might be helped by stem-cell therapy, you would need tens of millions of donated eggs--a wildly unrealistic number. Indeed, say ethicists, the limited supply of eggs could restrict therapeutic cloning to the relatively well off, as is the case with in vitro fertilization today. To help a significant number of victims, scientists may have to go beyond cloning and find other ways to get around the rejection response in conventionally produced stem cells.

By week's end the political storm over ACT's cloning baby steps had subsided. Senate majority leader Tom Daschle made clear that the cloning bill would not be taken up before Christmas, and Republican Arlen Specter, a proponent of stem-cell research, vowed he would do whatever he could to prevent a ban. But given the discomfort the word cloning tends to inspire, companies like ACT may think twice before letting a media frenzy get out of hand.