The decision to end many restrictions on embryonic stem cell research has removed a key barrier to research and discovery. Scientists are driven by the desire to succeed as fervently as our most success-driven businessmen, entrepreneurs, or lawyers. But for years they have contended with research limits that prevent innovation but do not serve a clear moral purpose. A responsible expansion of embryonic stem cell research can advance a vital goal—the search for new medical treatments—while respecting the dignity of human life.
At present, there are about 400,000 human embryos in the freezers of in vitro fertilization clinics. Many are destined to be thawed and discarded and thus die. It is a true moral dilemma, but science offers a way to bring something good from a flawed situation. The parents of these embryos could allow them to die, or they could donate the embryos for research that someday might benefit patients with incurable diseases. This is a high purpose, one that promotes both human health and understanding.
Scientists have worked tirelessly to develop useful alternatives to these rare sources of embryonic stem cells. Through trial and error, they have developed a cocktail of genes that can transform adult human skin cells (from you and me) into cells closely resembling embryonic stem cells. But make no mistake—these are not embryonic stem cells. They are induced pluripotent stem cells.
The study of these cells is in its infancy. The hope is that induced pluripotent cells could be developed from individuals who have genetic disorders like juvenile diabetes, Parkinson's, and muscular dystrophy. Having stem cells with these defects could dramatically help scientists in their efforts to understand the basic, underlying problems in cells with these mutations. That's because stem cells offer a unique window into cell development—and they can shed light on how development goes awry in serious diseases. However, investigators also desperately need embryonic stem cells developed from patients with these genetic disorders to confirm that studies with induced pluripotent cells faithfully reproduce the genetic disorders. Scientists in the United States have developed such cell lines from embryos with genetic defects that were identified by genetic analyses. They have developed cell lines using money from private philanthropy because they have been prohibited by the previous administration from using federal money to carry out this important research.
Today, scientists are free of this impediment. But like all research, work on stem cells needs firm ethical guidelines. That's why scientists have joined with ethicists, lawyers, and patient advocates to develop the very strict rules that are currently in place to govern this area of study. I was part of a multidisciplinary group under the auspices of the National Academy of Sciences that met numerous times to develop guidelines that help ensure such work proceeds only within well-defined limits. The rules were adopted by California in 2005 to guide its stem cell initiative, and they have since been modified in response to California law and vigorous public debate.
One of the guiding principles in these policies is the intrinsic value of human life. The guidelines call for careful ethical oversight of all research using human oocytes (eggs), embryos, or cell lines derived from these tissues. The cells and embryos must be obtained with informed consent, with no money paid for oocytes or embryos. All proposed research must be reviewed by a separate board that has scientists who are knowledgeable about embryonic stem cell research, as well as ethicists and the lay public. These representatives make certain that, for example, California's Institute for Regenerative Medicine, a state agency created by a 2004 stem cell research ballot referendum, supports only projects that advance knowledge and specifically require the use of human embryos—a high standard that ensures respect for human life. The embryos can be cultured for only 12 days under California's rules, meaning they never develop complex structure—a provision that many ethicists believe is important to prevent future experimentation on more mature embryos.
Corrected on : Janet Rowley is a professor of medicine at the University of Chicago and a member of the President's Council on Bioethics.