A Cluster of Ethical Questions
Consider the blastocyst. It's a microscopic clump of cells that looks as innocuous as a raspberry. Yet, because the blastocyst is destroyed to extract those cells — which have the ability to grow into any of the 200 types of tissue found in the body, offer hope to sufferers of incurable diseases, and lead scientists into new frontiers of medical discovery — the tiny clump has stirred up a big batch of trouble.
Since human stem cell research began in earnest a little more than a decade ago, the blastocyst — an embryo five days to two weeks old — has represented more than the possibility of hope for scientists. Anti-abortionists, religious groups, and at least one prominent Johns Hopkins faculty member say a blastocyst also represents a human life and should therefore be treated as such — meaning, they should not be objects of research.
"These are fertilized cells that are alive," says Paul McHugh, a professor of psychiatry and behavioral sciences at the School of Medicine. "Everybody knows when life begins — at conception — unless they have political reasons not to believe it."
There's a political dimension to McHugh's views as well: George W. Bush, author of a ban on federal funding for research involving all stem cell lines created from blastocysts after August 2001, named him to the President's Council on Bioethics, a body with the power only to make recommendations, in 2002. (Since then, Benjamin Carson, a professor of neurosurgery at the School of Medicine, has also been named to the council, which will continue to meet until its scheduled dissolution in September.)
Researchers who say a dearth of federal funding has hampered their work counter that embryos are not yet fully "human" subjects because their cells have yet to show signs of organization. Embryos don't begin to form a nervous system until they reach the age of 14 days. Researchers typically extract stem cells at about five days from blastocysts that are left over from efforts to artificially impregnate women after embryos have been grown in a dish. Mining for stem cells destroys the blastocyst, which, scientists argue, would otherwise have been tossed out as medical waste. As many as 250,000 such embryos are available at any time — more than enough to advance stem cell science, says Chi Dang, vice dean of research at Johns Hopkins. Those who oppose research performed using embryos continue to worry, however, that embryos may still be created specifically to be research tools.
"There's a fair amount of debate on campus about embryonic stem cell research," says Debra Mathews, assistant director for science programs at the Johns Hopkins Berman Institute of Bioethics. "The vast majority of people are not at either end of the spectrum."
Still, McHugh's perspective is rare here. Researchers overwhelmingly favor leaving all doors of inquiry open, as do Hopkins administrators and the National Academy of Sciences. However, they disdain any attempts at using stem cell technology to clone humans.
But the debate has shifted away a bit from the binary one over embryos and toward a more nuanced discussion on how to ethically handle research that involves so-called induced pluripotent stem cells (iPS cells), which were discovered two years ago. While the university's Embryonic Stem Cell Research Oversight Committee, formed in 2006, continues to set ethical standards for scientific investigation and to make sure that stem cells derived from blastocysts are used safely, scholars at the Berman Institute have expanded their purview to include iPS cells — adult cells that can be taken from the skin and elsewhere and then reverted back to their stem cell form.
Hopkins bioethicists have published several papers on a number of ethical flashpoints that arise when all types of stem cell research are factored in, including when stem cells are derived from the blood of the umbilical cord after birth. Who will be empowered to give consent for the use of umbilical cord blood in research? If post-birth tests of the blood reveal that a baby or parent has a disease, such as HIV or hepatitis, how will their privacy be protected if the cells are used in future research? Will people use stem cell-based treatments not for medical reasons but to enhance their lives, such as by taking a pill usually prescribed to regenerate brain cells in stroke patients, to pump up SAT scores by a few points? Will stem cell treatments be available to all of the public, or merely the well-heeled — perhaps creating a permanent biological underclass?
Ethicists generally are wary of reliving the debate over the embryo, as would happen if the nucleus from one iPS cell were implanted in an embryo for the sake of harvesting stem cells from it (or for cloning humans). They also urge restraint on creating so-called chimeras — nonhuman mammals that have been genetically altered to have some human attributes (like, say, a chimpanzee with parts of the human brain).
While scary scenarios worthy of Michael Crichton novels abound in the imaginations of some people, Hopkins ethicists say it's likely that most of the issues surrounding stem cell research will be worked out before human trials become a regular part of the research landscape.
"We're always afraid of new sources of power," says Jeremy
Sugarman, SPH '92, a professor of bioethics and medicine at the
Berman Institute. "Mesmer was scared of magnetism. Mary Shelley,
in Frankenstein, showed we were afraid of electricity. Then you
have the radiation fears in Spiderman comics. Now, we have
biologics. You'll always see these fears pop up in fiction. But
we usually deal with them in real life, and then move on."
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