A Lamb Ignites a Debate On the Ethics of Cloning
Theologians say it interferes with natural order of creation
BOSTON AND WASHINGTON
From the White House to the farm house, a lamb named Dolly is coming to symbolize the moral and ethical minefields sown by genetic engineering.
Researchers in Scotland stunned the scientific community during the weekend when they announced that seven-month-old Dolly was cloned from cells taken from an adult ewe. If the results are confirmed, they open up the prospect of "designer" offspring picked from a catalog of existing adults with the desired genetic traits.
To many researchers, that ability could revolutionize cattle and dairy farming, as well as the use of animals as walking biomedical chemical factories. To several scientists and theologians, however, that ability - if applied to humans - could have disastrous social and cultural consequences.
"This is a giant leap in technology," observes Robert McKinnell, a geneticist at the University of Minnesota and a noted authority on cloning. "The few people who think human cloning is a good idea are that much closer to their goal."
The notion that technology is getting ahead of ethics and the law "has become almost like a mantra," adds Thomas Murray, director of the Center for Biomedical Ethics at Case Western Reserve University and a member of the National Bioethics Advisory Commission (NBAC). "This time it has a kick to it."
Theologians and ethicists raise three broad objections.
* Cloning humans could lead to a new eugenics movement, where even if cloning begins with a benign purpose, it could lead to the establishment of "scientific" categories of superior and inferior people.
* Cloning is a form of playing God, since it interferes with the natural order of creation.
* Cloning could have long-term effects that are unknown and harmful. People have a right to their own identity and their own genetic makeup, which should not be replicated.
Although their work has stirred a firestorm of debate, the Scotland team's results may be less sweeping than they first appear, some researchers suggest. In an analysis appearing in the Feb. 27 issue of the journal Nature, where the cloning work is being published, Colin Stewart, a scientist with the NCI-Frederick Cancer Research and Development Center in Frederick, Md., notes that two factors governing the development of cells in sheep embryos may limit the new technique to sheep.
"The results are intriguing, but I can't get too excited about them," adds Michael Altherr, a geneticist at the Los Alamos National Laboratory in New Mexico. The problem, he says, is that the team fails to make a convincing case that it has succeeded in cloning Dolly from adult cells.
As part of a larger experiment, the group, led by Ian Wilmut of the Roslin Institute, a nonprofit livestock research laboratory in Roslin, Scotland, removed the DNA from the nuclei of ewes' eggs. Then researchers took cells from a mature ewe, deactivated the DNA in their nuclei, and fused the cells with the eggs. The DNA from the mature cells moved into the eggs' vacant nuclei, reactivated, and when the researchers added a jolt of electricity, the modified eggs began to form embryos. As the embryos grew, the researchers implanted them in ewes to bring them to term.
Out of an initial 277 of these cell-egg pairs, only 29 resulting embryos made the implantation team. Out of those 29 implanted into ewes, only one lamb was born, yielding a 3.4 percent success rate, according to the Scottish scientists. Seven other lambs were born, but their embryos did not originate with eggs fused with material from adult cells.
"Science is based on reproducible results," Dr. Altherr notes. With only one lamb, he says, the door is open to other plausible explanations for the lamb's genetic makeup, other than cloning from an adult cell. "But if they are right," he says, "then it does open up the discussions we're hearing about the implications."
Those discussions aren't waiting for a final verdict from the lab. On Feb. 24, President Clinton asked the NBAC to assess the impact of cloning technology following Wilmut's announcement and to report to him in 90 days.
"I don't known that the issues have changed much from the '60s or '70s," says James Gustafson, a professor at Emory University's Candler School of Theology. "Now we have cloned a [mammal], whereas we used to clone a toad. But as far as cloning a human being goes, I don't think the moral arguments have changed any."
Scientists and bioethicists dismiss popular notions of cloning Einsteins or Michael Jordans. For one thing, clones are not carbon copies of one another; they can contain subtle physical differences, although they are genetically identical, Dr. McKinnell says.
Moreover, people are influenced by a range of relationships and environmental factors "that help determine who and what we are," says Dr. Murray. "Making a genetic copy of a person is not making the same person."
For Murray, the prospect of being able to conceive children asexually or with certain specifications must be seen in the context of "a broader cultural debate about the moral significance of parenthood. It's a wake-up call to think about what's really at the heart of what we value about the parent-child relationship."