Cloning: Where are the limits?

A sheep named Dolly brought the issue to the front pages, but doctors face far more intricate dilemmas than simply whether to create carbon copies.

Dorothy L. Pennachio
Senior Editor

Think you're against cloning humans? (Eight out of 10 of our 2002 Ethics Survey respondents say they are.) Well, Paul Root Wolpe, a bioethicist at the University of Pennsylvania School of Medicine, says reproductive cloning isn't as black and white as many people believe. He suggests considering these scenarios:

• Tom and Mary carry the gene for cystic fibrosis. They considered it a miracle when their daughter Jane was born without the disease and is not even a carrier. Jane is killed in an auto accident. Mary and Tom are pro-life and against preimplantation selection because they don't believe in discarding embryos. But they ask their physician to take a cell from Jane's body and clone it, not because they want a new Jane, but because if they were forced to go back into the genetic lottery, they'd probably have a child with CF.

• A young husband is burned to death in the Sept. 11 attack with no possibility of posthumous sperm retrieval. Parts of his body are found, and his devastated widow directs the physician to take a cell from deep inside his body and clone it so she can have his child.

"When people are asked in the abstract whether they are for or against reproductive cloning, they generally are revolted by the concept," says Wolpe. "But when faced with specific scenarios, they give very different responses."

We asked physicians how they feel about cloning, both reproductive and therapeutic (somatic cell nuclear transfer). Of the two in 10 who favor cloning of humans, cardiologists are most open to the procedure, and ob/gyns the least (30 percent vs 13). But 84 percent of all respondents say they favor cloning to produce stem cells for medical research. Should criminal penalties be imposed on physicians who violate a ban on cloning? Most, 56 percent, say Yes.

For the general public, the very word "cloning" sets off an alarm. They're even less accepting of the concept than physicians: Only 8 percent of Americans support reproductive cloning, according to a Gallup poll. Asked about therapeutic cloning, though, 59 percent say they favor cloning of human organs or body parts that can then be transplanted; 34 percent favor cloning of human embryos for use in medical research; and 51 percent favor cloning of human cells for use in research.

Last July, the President's Council on Bioethics called for a four-year moratorium on any human embryonic cloning for biomedical research, meant to allow time for a thorough federal review of the issue, perhaps allowing time for researchers to find other ways to generate stem cells. The vote on a total ban on cloning was split—of the 17 members, 10 recommended a ban on cloning-to-produce-children combined with a four-year moratorium on cloning-for-biomedical-research, and seven recommended a ban on cloning-to-produce-children, with regulation of the use of cloned embryos for biomedical research.

In the private sector as well, the cloning debate has proved a thorny issue for all involved, say bioethicists. Daniel Callahan at The Hastings Center says he's against stem cell research.

"I'm worried about the long-term implications of research cloning and see it as a slippery slope to genetic engineering of a disastrous kind," says the bioethicist. "Can we really say that if we don't do stem cell research, we'll never cure Parkinson's or Alzheimer's?" Callahan asks. "No, there are alternative means of research. Yes, research cloning is promising, but lots of science is promising. That doesn't mean you have to do it."

Callahan's is the minority view within The Hastings Center, however. "Most believe embryos don't have significant moral status or standing, and that their use for research could lead to many cures," he says.

One group that favors therapeutic cloning is the American Society for Reproductive Medicine. According to Sean Tipton, the society's public affairs director, research must be allowed to move forward because of its promise for improved approaches for treating spinal cord injury and degenerative conditions including Alzheimer's and Parkinson's disease.

Dorothy Pennachio. Cloning: Where are the limits?.

Medical Economics

2002;19:107.