The U.S. House of Representatives is set to vote Thursday on a bill that would ban all cloning, including therapeutic cloning, which some researchers believe is key to treatments for many deadly and debilitating diseases.
Social conservatives and the anti-abortion lobby have championed a ban on therapeutic cloning because 4-day-old embryos are destroyed in the process, a practice they believe is akin to murder.
The other side of the argument says hundreds of leftover embryos are discarded every week by in-vitro fertilization clinics, so why not use them for research that could lead to treatments for diseases like Alzheimer's, Parkinson's and diabetes?
Four of the top minds in the debate took the stage to argue their points at Time magazine's The Future of Life conference in Monterey last week. The experts were deeply divided on the issues surrounding therapeutic cloning, but even the most conservative of the bunch could not assert that it is better to throw embryos away than to use them for research.
"When a human being becomes a human being has nothing to do with stem cells because the issue is: Would you rather throw it away or use it?" said Wise Young, director of the W. M. Keck Center for Collaborative Neuroscience at Rutgers University.
While the vast majority of scientists oppose human cloning that results in a live birth, also known as reproductive cloning, many support therapeutic cloning.
In therapeutic cloning, researchers extract stem cells from 4-day-old embryos. Human embryonic stem cells are master cells that can grow into almost any tissue in the body. Scientists hope to guide this growth to create replacement cells that could treat or cure diseases that involve the destruction of cells -- anything from Parkinson's disease to spinal cord injury. By using stem cells taken from a clone of the patient, scientists believe they might avoid rejection of the cells by the body's immune response.
The assumption that therapeutic cloning is key to the success of embryonic-stem-cell therapies (none of which have yet been shown to work) has permeated the stem-cell debate and the cloning debate.
On Aug. 9, 2001, President Bush declared that scientists who receive federal research funds could work only with the 60 or so stem-cell lines that had been created before that day. In reality, however, the number of usable lines turned out to be fewer than 10.
Michael Kinsley, panel moderator and founding editor of Slate, pointed out a contradiction in that the president does not oppose in-vitro fertilization, which results in the destruction of thousands of embryos, yet he is against therapeutic cloning for that very reason.
"I think it's inconsistent, and I'm in full agreement with you," said Alfonso Gomez-Lobo, professor of metaphysics and moral philosophy at Georgetown University and a member of the President's Council on Bioethics.
John Gearhart of Johns Hopkins School of Medicine, one of the leading stem-cell researchers in the country, says cloning may not be the savior of stem-cell therapies after all.
"I don't know that nuclear transfer (that is, cloning) is going to be the answer to getting around the immune response question," he said at the Future of Life conference.
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