New York Times
November 26, 2001
Company Says It Produced Human Embryo Clones
By GINA KOLATA
A small, privately financed biotechnology company said yesterday that it had created the first human embryos ever produced by cloning. But the embryos died before they had even eight cells, and most died long before that. Cloning experts outside the company said the experiment was a failure.
But by pursuing the research and publicizing it, scientists at the company, Advanced Cell Technology in Worcester, Mass., have stepped into an ethical controversy. Federal money cannot be used for cloning research involving human embryos, and so the experiments are restricted to the private sector.
Advanced Cell Technology was not trying to clone a human being. Rather, it wanted to offer a method that would involve combining human eggs and a person's own cells to create embryos that would provide stem cells. Theoretically, the stem cells could in turn grow into virtually any cell type and serve as replacement tissue in diseases like diabetes.
Such therapeutic cloning would have the advantage that the replacement tissue would be an exact genetic match, so patients would not have to take anti-rejection drugs. But the idea has raised ethical concerns because it would require destroying a cloned embryo to extract its stem cells.
In July, the Advanced Cell Technology revealed that it had been secretly working on therapeutic cloning for a year, paying young women $3,000 to $5,000 for eggs and using them to try to create human stem cells. Its experiments, financed with private money, raised questions about whether science was moving ahead of public policy.
The new paper on the cloning, published in E-biomed: The Journal of Regenerative Medicine, describes the results of those studies.
Advanced Cell Technology used two different methods to try to create human embryos. The first was much like the standard approach that has been used to clone cows and sheep, including the first cloned sheep, Dolly. It involves taking the genetic material out of an unfertilized egg and inserting in its place an adult cell, which has a full complement of genetic material. The resulting clone is an exact genetic copy of the donor of the adult cell — not the donor of the egg.
In its experiment, the company replaced the genetic material of a human egg with that from adult cells, in this case either skin cells or cumulus cells, which are cells that cling to human eggs and that might be more amenable than skin cells for cloning.
The researchers started with 19 eggs, adding skin cell genetic material to 11 and cumulus cell genetic material to the rest. The eggs with skin cell genetic material died before they could even divide a single time. Three of the eight eggs with cumulus cells divided once or twice before dying.
It was impossible to retrieve stem cells. An embryo would have to grow for about five days and, more important, from a ball of cells into a vesicle with two cell types. One type makes up the outer wall and the other type clusters inside and consists of embryonic stem cells.
The second method was to stimulate an egg to divide without being fertilized. Any embryos that might result from this process, known as parthenogenesis, would have only the genes of the egg cell. But they cannot develop into babies — genes from a male are needed to form a functioning placenta. Dr. Michael D. West, the company's chief executive and an author of its paper, said that since the embryos had no hope of developing fully anyway, he hoped there would be no ethical objections to destroying them to get stem cells.
In the parthenogenesis experiments, the scientists at Advanced Cell Technology started with 22 human eggs, chemically stimulating them to divide. Most died within a day or so. Six lasted for five days, but, as in the other experiments, the embryos died before forming stem cells.
Dr. West said he was encouraged even though the experiments did not provide the stem cells the company sought. "We're optimistic," he said in a telephone interview.
But some scientists were not impressed. "It's a complete failure," said Dr. George Seidel, a cloning expert at Colorado State University in Fort Collins. For a first attempt, he added, "they've progressed about as well as you'd expect, or slightly worse." Dr. Steen Willadsen, a cloning pioneer in Windermere, Fla., said, "If one were to take a positive view of this, then one would say there are some problems with the approach they are taking — it hasn't worked."
Some lawmakers want to ban the research entirely.
Senators Richard C. Shelby, Republican of Alabama, and Patrick J. Leahy, Democrat of Vermont, reacted with dismay to the company's claims that it had created cloned human embryos. But Senator Richard G. Lugar, Republican of Indiana, was cautious in an interview with "Late Edition" on CNN. "We really ought to take it on the basis of much more thorough understanding than this first report," he said.
Senator Tom Daschle, Democrat of South Dakota and the majority leader, said he supported cloning of this kind for research purposes. But Mr. Daschle added that he would oppose any human cloning intended to replicate a person, and said such an effort would face overwhelming opposition in Congress if it were ever proposed.
President Bush has said he is opposed to the type of cloning described in the announcement today.
But in its press release, the company was enthusiastic. The paper "provides the first proof that reprogrammed human cells can supply tissue for transplantation," the company said. The press release quoted Dr. Robert P. Lanza, the company's president of medical and scientific development and an author of the paper.
"These are exciting preliminary results," Dr. Lanza said. The company's scientists also wrote a paper for Scientific American, which appears on its Web site today, called "The First Human Cloned Embryo."
"After months of trying, on Oct. 13, 2001, we came into our laboratory at Advanced Cell Technology to see under the microscope what we'd been striving for — little balls of cells not even visible to the naked eye," the scientists wrote. "Insignificant as they appeared, the specks were precious because they were, to our knowledge, the first human embryos produced by the technique of nuclear transplantation, otherwise known as cloning."
The paper goes on to say these embryos died. But then the article returns to the promise of the method