Second opinion

To be or not to be

Is a fertilized egg equivalent to a person? Ernlé Young, PhD, former chaplain to Stanford's medical center, professor of medicine emeritus and co-founder of Stanford's Center for Biomedical Ethics, spells out the central controversy generated by the medical use of embryonic stem cells.

By ERNLE YOUNG

Is there an ethical argument for the use of human embryonic stem cells? I think there is.

Stem cells that come from human embryos offer great medical promise. But their use in research and treatment stirs up great debate -- far greater than stem cells from other sources: umbilical cord blood, adult tissues and even fetal tissue.

Let's take a look at this most controversial source.

Most human embryonic stem cells used in research come from fertilized eggs that were frozen upon reaching one week of development. These embryos, frozen in the blastocyst stage, consist of a hollow ball of a few hundred cells, measuring about two-tenths of a millimeter across.

The use of these stem cells brings into question the blastocyst's moral status. Here, there are two opposite views, each reflecting a different notion of personhood -- what it means to be a person. University of British Columbia bioethicist Walter Glannon, PhD, describes one view, writing: "The criteria of being a person, which consist of mental states caused by certain brain and bodily functions, are more complex than the criteria of being human, which involve brain and bodily functions but not those necessary to generate and sustain mental life. This implies that persons are not identical to human organisms, or human beings. Although the two terms sometimes are used interchangeably, person is a psychological concept, while human is a biological concept." (Walter Glannon, Genes and Future People. Cambridge, Mass.: Westview Press, 2001, page 22, italics added.)

A second view makes no distinction between being human and being a person but rather equates the two. Thus, from the moment of conception, the fertilized egg is believed to be fully a human person. Like all persons, it is therefore entitled to the protections from wanton harm or destruction that society affords. Coming from this perspective, to kill a blastocyst is to murder a person, even if destroying the blastocyst is done for some noble end like stem cell research, in the hope of saving the lives of those who already exist.

There are at least five weaknesses in the assertion that the blastocyst is a fully human person:

  1. Until the blastocyst actually implants in the uterus (seven to eight days after conception), it cannot possibly develop into a person.
  2. Even after implantation, up until about 14 days' gestation, natural "monozygotic twinning" can occur. In this case there would be two "persons" rather than just one.
  3. Even after implantation, spontaneous abortions can occur. In the normal course of human reproduction, about 60 percent of embryos spontaneously abort and are simply flushed in the course of the menstrual cycle. In in vitro fertilization, about 75 percent of the blastocysts either fail to implant or are lost through spontaneous abortions.
  4. Even after implantation, in rare cases the blastocyst can develop, not into a human being, but into a tumor called a hydatiform mole.
  5. A biological concept (being human) is being used as equivalent to a psychological concept (being a person).

If we take these five objections seriously, we must modify the assertion that the blastocyst is a person by saying that even if it is not an actual person, it is potentially a person.

But is potentiality the same as actuality? I think not. You and I are potentially dead. But we are not yet actually dead and until we actually die it would be a mistake to treat us as if we were dead. Potentiality is not equivalent to actuality.

The alternate view, stated at this essay's beginning, recognizes a distinction between being human (a biological concept) and being a person (a psychological concept). Thus, the blastocyst or embryo is a human organism, but not a person. It does not even become a potential person until the emergence of a rudimentary central nervous system -- something which is thought to happen at about 26 weeks of gestation. Therefore, as Glannon puts it, "Since embryos … do not have the requisite biological structures to generate and sustain the mental capacities necessary for interests, embryos … cannot be benefited or harmed."

Thus the battle is joined between those who are opposed to stem cell research because they believe that the blastocyst is a person and those who favor stem cell research because they take the position that the blastocyst is not.

This is the crux of the ethical controversy.

For myself, the promise of concrete medical advances for real people outmeasures any concern over the possibility of harm to non-persons.

In surveying the policies of governments, it would seem that there is a greater future for stem cell research in the United Kingdom and Australia, as well as Asian countries such as Singapore, South Korea and the People's Republic of China than there is here in the United States under the current administration. This suggests that we may lose our present lead in this exciting new field and, worse, also lose many of our top scientists as they go to work in countries more hospitable to this research than we appear to be. Roger Pederson, PhD, for example, was formerly at the University of California-San Francisco; he has emigrated to the United Kingdom to continue his stem cell research at Cambridge University. Regrettably, he may be the first of many who leave.

I find this ethically troubling. In a pluralistic society such as ours, no single set of moral certainties, ideological convictions or religious beliefs ought to pre-empt, let alone prevail over, other points of view. Yet this seems to be happening. We are witnessing a resurgence of religious conservatism wielding political power to an unprecedented extent. The future not only of stem cell research but also of all our democratic freedoms may well be at stake.

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