While stem cell research has the potential to change the face of medicine, it also raises a number of ethical, halachic, legal and cultural questions, said Dr. Avraham Steinberg.
Steinberg, an ordained rabbi, is a pediatric neurologist and an international expert in Jewish biomedical ethics. He is director of the centre for medical ethics at the Hebrew University-Hadassah Medical School and director of the medical ethics unit at Shaare Zedek Medical Centre, both in Jerusalem. He is the 1999 winner of the Israel Prize.
His recent lecture on stem cells was part of a scholar-in-residence program at Beth Avraham Yoseph of Toronto Congregation.
Stem cells are immature, undifferentiated cells that can develop into any cell found in the human body. However, once cells mature, they lose that ability, Steinberg said.
Stem cells currently used for research come from two sources – unused or rejected eggs from in vitro fertilization procedures or from a miscarried or aborted fetus, he said. Occasionally, he added, they may come from amniotic fluid or umbilical-cord blood.
Stem cells from bone marrow have been used for some time, and it is hoped that they will also be useful in treating Parkinson’s disease, Alzheimer’s disease, stroke and diabetes.
If the potential for good is so high, why, then, is there so much controversy?
Steinberg said that the ethical and legal objections to stem cell research mainly boil down to the question of when life begins and the question of what is life.
“It is not a scientific matter. It is cultural, ethical and social. If society says that life begins at five, then that’s when it begins,” he stressed.
Life may be considered to begin at different stages of development – conception, implantation, 14 days, 40 days (the Jewish concept), the first fetal movement, when the fetus becomes viable, or the moment of birth.
Is using a fetal cell acceptable when it is for important, life-saving purposes? When it would be thrown out anyway? Most significant are the questions of whether destroying a stem cell is murder; whether it is acceptable to destroy a cell for a greater good; and whether using these stem cells encourages abortion, Steinberg said. All these questions concern both the general population and the scientific community, he added.
Politics, Steinberg said, has entered the equation, too. Germany, Norway, Argentina, Poland and some U.S. states prohibit any use at all. In the United States, only stem cell lines (families of cells derived from a single, original stem cell) created before 9 p.m. on Aug. 9, 2001, are acceptable, and research on them receives federal funding. The problem is that after so long, many of these lines are defective and useless, Steinberg said.
This is not merely a theoretical problem, he said, as research into stem cells requires an enormous amount of money – too much to come from private or even corporate sources.
Religious opinions also differ on stem cell research, he said. Catholicism “absolutely prohibits it, just as it does contraception and abortion.” Protestant denominations are divided; Islam permits it.
In Jewish thought, there is the philosophy that the enhancement of knowledge enhances our belief in the Almighty, Steinberg said. “The more we know, the more we know the incredible thing God did [in creating the world].”
We are partners with God in healing the world. God left the world unfinished, for man to complete, Steinberg said. Those who are able to do something concrete, then, such as doctors and scientists, are not only allowed, but obligated, to do what they can, he noted.
On the other hand, research must not involve an inherent halachic prohibition; it must not lead to a prohibited result, and the benefit must surpass any detriment, he stressed.
Judaism recognizes that there is a difference between an embryo that is still in a test tube (such as for in vitro fertilization) and one that has been implanted into a woman’s womb. Inherent human rights are acquired in a progressive way, depending on developmental status.
“Each stage, however, has its own holiness,” Steinberg said.
Before implantation, a fertilized egg [in Halachah] has no human status. However, it is respected as a part of humanity and as potential life.
While Halachah allows fertilized eggs to be used for in vitro fertilization, creating fertilized eggs for research is not.
In cases of potential genetic problems, such as the presence of the gene for Tay-Sachs disease, testing fertilized eggs for the mutated gene and then implanting only the healthy ones, while disposing of the ill ones, is now done routinely, Steinberg said.
For instance, a carrier of the gene for neurofibramatosis (a set of genetic disorders that cause tumours to grow along various types of nerves and can affect non-nevous system tissues) was afraid to have children and so underwent the procedure.
Haredi Torah scholar Rabbi Yoseph Sholom Eliashiv said that in principle such a procedure is permissible, but only on a case by case basis, Steinberg said.
The procedure is done for serious reasons, “not, for example, because you want a blue-eyed child,” he added.