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The Complexities of Stem Cell Research

Proponents on both sides of this at-times controversial debate each make their case, combining the science, history, policy, and ethics of the research.

Published August 1, 2002

By Fred Moreno, Dan Van Atta, Jill Stolarik, and Jennifer Tang
Academy Contributors

Image courtesy of NIH via Wikimedia Commons.

Following the recent death of American baseball legend Ted Williams, it was learned that the former Boston Red Sox slugger’s body had been suspended in liquid nitrogen, encased in a titanium-steel cylinder along with other bodies being preserved at a commercial cryonics facility. Controversy swirled as the story circulated that at least one family member sought to preserve the icon’s DNA for possible future use in cloning.

Cryonics and cloning are the stuff of popular fiction and films from Frankenstein to Star Wars, with the scientist’s power to “create life” eliciting both fear and fascination. With cloning and embryonic stem cell research now poised for rapid expansion, however, the real-world debate on cloning, even for specifically defined therapeutic purposes, has heated up. Scientists, too, have begun to grapple with the issue of setting appropriate limits on their ability to engineer life.

Stuart Newman, professor of Cell Biology and Anatomy at New York Medical College, is among the more skeptical voices in the debate on human cloning. Speaking at a roundtable discussion held on the subject at The New York Academy of Sciences (the Academy) this spring, Newman called the creation of clonal embryos a slippery slope that no amount of regulation can level. He cited what he considers to be inexorable pressures on biomedical researchers to transgress acceptable limits by allowing cloned embryos to grow beyond the cellular stage.

The Thornier Aspects

During the meeting, which was co-hosted with Gene Media Forum, Newman engaged in an interchange with patient-activists – including the noted actor and director Christopher Reeve – and fellow scientists in an effort to sort out the thornier aspects of the cloning debate.

Craig Venter, PhD, president of the TIGR Center for the Advancement of Genomics and a major figure in microbiology and genomics, moderated the debate. Other panelists included Rudolf Jaenisch, MD, professor of Biology at MIT; James Kelly, an activist on behalf of spinal cord treatment; and Reeve.

For many, the cloning debate hinges on the distinction between reproductive and therapeutic cloning. Reproductive cloning aimed at creating a child has been censured by scientists and ethicists alike. Earlier this year, the National Academy of Sciences called for a total ban on human reproductive cloning, but strongly endorsed cloning to obtain stem cells that hold promise for curing a broad spectrum of human diseases. Jaenisch and Reeve expressed their support for this view, while Kelly and Newman cast doubt on the advisability of human cloning for any purpose.

Therapeutic cloning relies on nuclear transfer technology, a technique used to create a customized stem cell line for a patient in need. The nucleus of one of the patient’s own skin cells, for example, is extracted and transferred into a human egg whose nucleus has been removed. The new nucleus of this cell is then exposed to the egg’s signals, causing it to revert to its embryonic state.

In theory, embryonic stem cells can be chemically coaxed into producing lines of cells that will make whatever tissues are needed to heal and repair the body. Examples being considered include leukemia-free bone marrow cells, insulin-producing islet beta cells for diabetics, and dopamine-rich neurons for patients with Parkinson’s disease.

Commercial Interests and Patient Pressures

Still, the slippery slope looms large for critics of the new science. If a legal limit is eventually set allowing scientists to grow a clonal embryo for 14 days, Newman speculated, why not 15, 16, or 17 days and beyond? He said a combination of commercial interests and patient pressures would make it impossible to regulate the technology.

But Rudolf Jaenisch strongly disagreed with this all-or-nothing view. “It’s premature to ban a technique that is still in the process of evolving,” said Jaenisch, referring to a bill in the Senate that, if passed, would criminalize all forms of human cloning. “At no point in our nation’s history has Congress banned an area of scientific exploration or technology by federal legislation.” Nonetheless, despite the objections of many scientists, a total ban on cloning in the United States remains a distinct possibility.

European governments are generally recommending a more measured approach to regulating the new technology. The U.K. recently passed a law prohibiting reproductive cloning but allowing therapeutic cloning research to move forward under strict government oversight.

Australia, Canada, Israel, Japan, Portugal, Singapore and the Benelux countries also have approved therapeutic cloning. A special committee of the European Parliament has been holding meetings to develop a framework for cloning research that can help European governments evaluate its risks and benefits.

“The British solution is black and white,” said Jaenisch. “If you implant a cloned embryo into a uterus, it’s a criminal act. If you put it into a Petri dish with the intent of making an embryonic stem cell, it is allowed. There is no gray zone.” Again putting forth the slippery-slope argument, Newman pointed out that the development of an artificial uterus, for example, would nullify this distinction.

The Legality of Therapeutic Cloning

The United States is alone among the so-called developed nations in attempting to make therapeutic cloning illegal. If Congress succeeds in criminalizing all forms of cloning, the U.S. would effectively seal its borders against the importation of cloning-derived treatments for diseases that afflict millions of Americans. For those with Parkinson’s disease, diabetes, spinal cord injuries, Alzheimer’s disease, and a whole host of incurable conditions, this could be tantamount to “health exile.”

Despite their promise, however, cloning-derived stem cells and their successful development into cures are still just a distant possibility, according to James Kelly, who himself is confined to a wheelchair as a result of a spinal cord injury. They’re too uncertain, he believes, to warrant a large investment of research dollars at the expense of more tried-and-true avenues of investigation.

Christopher Reeve disputed Kelly’s assertion on two counts: First, in his view, it won’t be that long before therapeutic cloning techniques will be ready for use in humans; and second, biomedical research isn’t a zero-sum game. Pointing to the recent doubling of the NIH budget and to funds that have been earmarked by the Department of Health and Human Services for therapeutic cloning, he claimed there will be sufficient funding for many types of research.

The Promise of Therapeutic Cloning

Reeve, who was paralyzed in an equestrian accident in 1995, believes his best hope for recovery lies in therapeutic cloning. Because spinal cord injury usually leads to a compromised immune system, his doctors say his best option is treatment with embryonic stem cells derived from his own DNA, as cells from an anonymous donor would pose a high risk of rejection.

The charismatic activist and philanthropist further reminded his fellow discussants, and the audience, that scientific breakthroughs are often greeted with suspicion. “When vaccines became available early in the 20th century, there was a real fear and, in fact, strong opposition from the private sector and the government,” he said. “The idea for a vaccine against, say, measles meant the introduction of a small amount of measles into the patient, and people couldn’t comprehend that that would be actually the solution to contracting measles.”

Venter concluded the meeting by seconding Reeve’s warning against allowing fear to shape today’s attitudes toward scientific advances, stressing the inherent value of cloning research itself. “Just doing the basic science research is one of the greatest avenues we’re ever going to have to understand our own development and our own biology,” he said

Also read: :The Tantalizing Promise of Stem Cell Research


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