Feb. 22, 2000 (Washington) -- Using existing cultured human embryo cells for research purposes is morally acceptable, according to representatives of several prominent bioethics committees. But the ethicists disagreed about whether it is appropriate to create new cells from very early human embryos.
The panelists discussed controversial issues related to human embryo cell research in Washington Tuesday at a symposium of the annual meeting of the American Association for the Advancement of Science (AAAS).
The specific cells that the panelists discussed are called "stem cells," and they are cultured human cells that have the potential to develop into almost any of the body's different tissues, such as bone, heart, or brain tissue, according to John Gearhart, PhD, professor of gynecology and obstetrics at the Johns Hopkins School of Medicine in Baltimore. Such cells can be obtained from certain tissues in adult humans, such as bone marrow, and from very early human embryos.
Scientists believe that stem cell research could lead to a variety of new therapies that might be able to repair damaged or diseased organs, says Thomas Okarma, president and chief executive officer of Geron Corporation, a company that funded much of the early research on human embryo stem cells.
Currently, "we are powerless to urge a diseased or damaged organ to repair itself," Okarma says. "That's the excitement, and that's the potential of this technology."
Gearhart says that stem cells from human embryos are different from stem cells derived from adult tissues, and are better suited for both research and medical purposes. That's because these cells generate youthful tissue rather than aged tissue and are therefore better suited for tissue repair.
But some people, particularly those with pro-life views, think that cells derived from human embryos should neither be created nor used for medical purposes, regardless of the potential medical benefits, says Ronald Green, PhD, director of the Ethics Institute at Dartmouth College in Hanover, N.H. Green was a member of a panel convened by AAAS to tackle these thorny ethical issues.
Both scientists and ethicists distinguish between two types of embryonic stem cells: those obtained from very early human embryos produced by fertilization in a test tube, and those produced by sperm or egg cells in the early stages of development obtained from electively aborted fetuses,
Among the questions the panelists discussed was the issue of whether it's all right to use existing stem cells for research. "What is the moral status of human ... stem cells?" Green asked. For most ethicists, he says, "this is not a particularly troubling question." That's because such cells lack the ability to produce a living human embryo, he says.
But ethicists disagreed about whether it was acceptable to destroy a living human embryo, even one with just a handful of cells, in order to create new cells, says Mark Frankel, PhD, of AAAS, who presented the AAAS panel recommendations. The AAAS panel recommended that researchers be able to use existing cells, but declined to recommend the creation of new ones.
Not all ethicists agree, however. A panel of prominent ethicists called the National Bioethics Advisory Commission (NBAC), which was appointed by President Clinton, concluded that such research was acceptable under certain conditions, says Thomas Murray, PhD, president of the Hastings Center and a member of NBAC.
Cell-based therapies based on this science could ease the suffering of many, Murray tells WebMD.
After consulting with scientists and a variety of religious representatives, NBAC recommended that Congress ease its prohibition -- which has been in place since 1995 -- on using federal funding for such research. That's because research funded solely by private companies, as it is now, would not necessarily generate the knowledge and potential therapies that the public could otherwise gain. If research is only done in the private sector, finding future medical benefits could be delayed, Murray says.
Gearhart and other panelists also emphasized the need to clear up several public misconceptions about the technology. Using human stem cells for research is not human cloning because the cells can't generate a human being. And none of the technologies will enable humans to live forever.
- The use of cultured human stem cells holds promise for new treatments of many different diseases and injuries because of the cells' ability to repair tissue.
- In order to get these stem cells, scientists must use parts of an aborted fetus or fertilize a human egg in a test tube.
- Not all ethicists agree on how stem cells should be obtained or used and whether the government should fund this type of research.