Embryonic War

It was heralded as a scientific milestone. Published in an advance online version of the scientific journal Nature, it was touted on the front pages of newspapers across the country. For the first time, scientists said last week, they had derived human embryonic stem cells using a technique that does not harm the embryo--a biological feat intended to assuage religious conservatives and break the impasse over federal funding of new embryonic-stem-cell research. "Up until now, embryonic-stem-cell research has been synonymous with embryo destruction," said Dr. Robert Lanza, the study's lead author and vice president of research and scientific development at the biotech firm Advanced Cell Technology (ACT). "I think this changes that paradigm."

But within days of publication, that wasn't so clear. A more careful examination of Lanza's work showed he'd only proposed a new method, but hadn't in fact proved it worked from start to finish. And, by relying on human embryos, he still couldn't avoid the inevitable firestorm. Publicly, the White House took a measured approach, calling the reports "encouraging." Some social conservatives, particularly Roman Catholics, were far more critical. Though they claimed a moral victory, saying their hard-line position had forced scientists to consider the ethical status of the embryo, they dismissed Lanza's approach. "We're against manipulating, harming, assaulting embryos for their cells even if it doesn't always kill them," says Richard Doerflinger, of the U.S. Conference of Catholic Bishops, who accused Lanza of deceiving the public about the details of his work. By late last week, the scientific "breakthrough" had failed to bridge the political gap.

Normally, embryonic stem cells are grown from embryos at the blastocyst stage, when they're clusters of about 150 cells. In the process, the embryos are destroyed. Borrowing from a fertility-clinic technique called preimplantation genetic diagnosis (PGD), which is used to screen for genetic diseases in embryos before implantation, Lanza extracted single cells out of 16 embryos, then grew two of those cells into new embryonic-stem-cell lines. While the experiment showed that it is theoretically possible to grow embryonic-stem-cell lines and still preserve the embryos, Lanza failed to prove this. He needed so many individual cells (total: 91) to create his lines that multiple cells had to be pulled from each of the embryos; in the end, all 16 were destroyed. Lanza says that single-cell extraction has been proved effective through PGD (embryos subjected to the loss of a cell have developed into healthy babies); more important, he says, he has shown that single cells can develop into embryonic-stem-cell lines.

Other scientists say Lanza's work is impressive. It's "an interesting and important technical feat," says Dr. George Daley, a Harvard stem-cell researcher. But there are still a host of unanswered technical questions, say Daley and others. And it's unclear how many scientists will rush to replicate Lanza's work--the key to deeming it scientifically solid. Already, scientists can derive many more stem-cell lines through traditional methods. And many researchers want to study "disease-specific" embryonic stem cells for disorders like Alzheimer's and diabetes, which Lanza's approach wouldn't allow.

Underlying all of this, however, is a deep discomfort that scientific research is being designed to appease religious or political concerns. Glenn McGee, a bioethicist at Albany Medical College in New York, says ACT's research--done by a for-profit company--is a "pitiful attempt to look morally acceptable, rather than do valuable science." Politically, says McGee, who resigned from ACT's ethics board in 2000 because he says he wasn't consulted about critical research, "this will never sell."

George W. Bush has steadfastly refused to fund any research on stem-cell lines created since he established his policy in 2001 and, in July, when lawmakers in both parties passed a bill to fund new lines, he issued his first presidential veto. There's no indication that he'll change his position any time soon. But if Lanza's technique eventually works without destroying embryos, Bush might be able to embrace it. "I think it would satisfy the ethical concerns," says former Bush adviser Jay Lefkowitz, who helped formulate the 2001 policy.

Still, it's unlikely to satisfy many social conservatives. They oppose the PGD process, which weeds out defective embryos. And they worry that a single cell could itself grow into a viable embryo. "Then we'd be back in the same soup"--destroying potential life--says Princeton professor Robert George, a Catholic bioethics adviser to the White House.

Lanza is used to the criticism. In 2001, ACT was accused of hyping a report on cloning human embryos. Lanza, who wasn't running the lab at the time, defends the science but says he would have handled things differently. Now he's charting his own course. At 50, he lives on an island in a Massachusetts pond and claims a collection of natural curiosities, including a 3,500-pound amethyst and a six-foot Brachiosaurus femur. Of McGee and other critics, he says his goal is to advance science: "I've done what I thought was right." But in the murky waters of stem-cell science, what's "right" is never crystal clear.

Embryonic War | News