Stem cells are "general purpose" cells out of which the cells specialized to particular organs develop. Stem cells could, in principle, be used to "grow" human organs for transplant purposes. The thereapeutic potential of stem cells is considered enormous, but, for the most part, not imminent; stem-cell research is at the basic- rather than applied-science stage.
For research purposes, embryonic stem cells, found in fertilized ova of a few days old, are greatly superior to adult stem cells. The usual source of embryonic stem cells is embryos created for use in vitro fertilization. More are created than are used to produce a fetus, and the surplus embryos are stored for future use or destroyed. Stem cells can be extracted from these ‚Äúexcess‚Äù embryos, but, thus far, not without destroying the embryo.
In a thoughtful speech in August 2001, President Bush laid out the pros and cons of continued stem cell research. The principal pro is obvious: the therapeutic potential of stem cells. (Later I'll give some additional reasons why we shouldn't want to discourage such research.) The cons are ethical in nature. Many religious people believe that a fertilized human ovum is a human being and they therefore regard the extraction of stem cells from the embryo, when it causes the embryo's destruction, to be murder, just like therapeutic (as distinct from spontaneous) abortions. Miscarriages are the best-known form of spontaneous abortion, but about half of all pregnancies are terminated by spontaneous abortions, most occurring before the woman realizes she's pregnant.
Some people who do not consider an embryo a human being nevertheless oppose stem cells research believe that the use of stem cells for therapeutic purposes would be the equivalent of cloning a human being in order to create spare parts to replace a person's organs as those organs become incurably diseased or wear out. They imagine a time when, if permitted, parents will clone their child at birth and use the clone as a source of replacement organs for the child. Other people oppose embryonic stem cell research because they oppose in vitro fertilization as tampering with the natural order of things.
It is not easy to deal analytically with arguments that are based on religion or emotion rather than on pragmatic considerations. Given the number of spontaneous (not to mention deliberate) abortions and the fact that in vitro fertilization, which produces excess embryos, is lawful, it is a little mysterious what exactly is objectionable about using some of these excess embryos, which would otherwise either be destroyed or stored indefinitely with dim prospects of ever being used to produce more in vitro children, unless the objector opposes all nonspontaneous abortion. And that is an opposition founded on religious belief. Some secular people oppose abortion as encouraging promiscuity, but that concern is inapplicable to the use of embryos as a source of stem cells.
The idea of cloning a child in order to have a spare source of organs--the idea that the clone's organs would be harvested, as needed, for transplantation into the child--is fanciful. To create organs from stem cells would not require creating an entire person. Moreover, whether a person originates as a clone (which is, for example, what an identical twin is), as a product of caesarean section, or in any other nonstandard fashion, it is still a human person with all the rights that persons have, including the right not to be killed just because someone else would like his organs. (I am of course assuming that an embryo is not a person for legal purposes.)
Bush concluded his August 2001 speech by announcing that he would oppose lifting the existing ban on federal support of stem cell research except with regard to existing stem cell lines, of which there were then 60, in laboratories scattered around the globe. Many of these lines turned out to be unusable for research purposes; today only 22 are left, which are too few to satisfy research needs. In response to this deficit Congress passed, but the President has now vetoed, a statute that would have lifted the ban.
Many countries, such as the United Kingdom and Singapore, not only do not share our qualms about stem cell research but want to make such research a major focus of their thriving biotech industries. Singapore recently lured leading American stem cell researchers to its major biological research center.
There are several economic points that spring to mind about the U.S. ban. The first is its futility, and this for two reasons. Since the researchers are not tied to any particular country, the maximum effect of the U.S. ban would simply be to shift all stem cell research to other countries; it would not stop the research and save the embryos. In addition, however, U.S. law does not ban stem cell research, but only the use of federal funds for that research. The main therapeutic applications of stem cell research lie too far in the future and are too uncertain to attract much private investment, given the high discount rates that most businesses use to evaluate projects. But there is plenty of state and especially private charitable spending on medical research, and so the ban on federal funding of this one area of medical research should merely cause a reallocation of research funds. More state and private money will go to stem cell research and more federal money to areas of research that will be receiving less state and private money because more of that money will be used for stem cell research.
But if the federal ban is not affecting the amount of financial support for stem cell research, why are many of our researchers going abroad to conduct that research? Why do countries like the U.K. and Singapore think they can steal a march on us? The answer may be that the U.S. research community does not think that opposition to stem cell research will express itself only in a ban on federal support for such research. Although the Supreme Court has recognized a constitutional right to abortion, it is unlikely to recognize a constitutional right to conduct stem cell research, even if the objections to such research are the same as the objections to abortion. The fact that the objections are primarily a product of religious belief would not invalidate them, because banning stem cell research does not infringe anyone's free exercise of religion or constitute an establishment of religion. Many moral precepts embodied in laws that no one supposes unconstitutional are the product of sectarian beliefs that secular people (or indeed religious people belonging to sects that are less influential in this country) reject. However, most of the precepts themselves, such as the taboo against murder, are shared by people of different, and of no, religious faiths; you don't have to believe that Moses brought the Ten Commandments down from Mount Sinai (you don't have to believe there was a Moses) to condemn murder. In contrast, opposition to abortion and stem cell research is not widely shared by people who do not belong to a particular subset of religious sects.
The loss of leading-edge biological researchers to other countries could be costly to the United States, especially if there are complementarities between stem cell research and other areas of biological and medical research. We may wake up some day to find that foreign institutions have obtained patent protection for highly lucrative medical therapies that our population will demand the government subsidize. I predict, however, that generous state and private funding of stem cell research will stem the reverse brain drain. (And if researchers are easily lured abroad, they are easily lured back.) Moreover, as therapeutic applications of stem cell research become more imminent, the pressure to relax the ban on federal funding is bound to give way.