Genetics and Reproductive Technologies

views updated

GENETICS AND REPRODUCTIVE TECHNOLOGIES

Modern genetics and technological aids to human reproduction, like other advances in science and technology, have created ethical problems heretofore unencountered. Biomedical developments have also posed new conceptual, epistemological, and metaphysical problems. This entry addresses these philosophical concerns as well as the more widely discussed ethical implications of contemporary genetics and reproductive technologies. One conceptual and ethical link between these two fields is the prospect of "designing our descendants." This prospect has been viewed by some as a boon to humankind (Fletcher 1974) and by others as a fearsome possibility to be avoided at all costs (Ramsey 1970).

The Human Genome Initiative, a "big science" project launched by the U.S. government to map and sequence the entire human genome, has heightened concerns about the privacy and confidentiality of genetic information, the uses to which such information might be put, and the possibility of stigmatizing individuals or groups because of their genetic constitution. The knowledge the Human Genome Project can yield is massive in contrast to previous efforts to acquire information about human genetics.

The contemporary science of genetics provides, not only an understanding of heritable traits, but also the capability to diagnose the probability or certainty of transmitting to offspring genetic conditions such as sickle-cell anemia. Tay-Sachs disease, or cystic fibrosis. The ability to identify and locate specific genes that render a person likely to manifest heritable conditions, such as Huntington's disease and certain forms of cancer, raises profound questions about the wisdom and desirability of learning about future contingencies when no cure exists and preventive measures are of uncertain efficacy.

A conceptual question is prompted by the rapid advances in genetics: What constitutes genetic disease? The traditional concept of disease relies on the ability of medical scientists to identify deviations from the normal physiological functioning of an organism. Asymptomatic diseases, such as hypertension, can be detected by diagnostic instruments even though the individual feels no symptoms of illness. With the discovery of genes that render an individual with a family history highly likely to develop a particular disease later in life, how should the individual who carries the gene be characterized? Does the person in whom the gene is found have a genetic disease or not? The individual has no symptoms and the disease may never express itself. Yet merely being susceptible opens the possibility of harm to the interests of such individuals, making them vulnerable to actions by others such as insurance companies who seek to deny insurance on grounds of a preexisting condition or employers who refuse to hire workers with a known propensity for illness.

Beyond the problems posed by diagnosis and prediction in genetics are those of intervention: Is gene therapy intrinsically different from traditional medical therapy? Even if gene therapy by means of manipulating somatic cells poses no special problem, what about altering germline cells, a procedure that would affect future generations? If genetic manipulation to correct defects is ethically permissible, what, if anything, would be wrong with alterations intended to provide genetic enhancement? Are efforts to improve human intelligence, appearance, or other attributes by genetic means essentially different from the traditional methods of education, physical or mental training, or behavior modification (President's Commission for the Study of Ethical Problems 1982)?

Attempts to improve the quality of the human gene pool, or "positive eugenics," have generally been viewed with disfavor, especially after the policies in Nazi Germany promoting racial hygiene (Proctor 1988). Yet eugenic practices remain at the level of individual choice. The recipients of donated sperm are typically given information about physical and other personal characteristics of donors, allowing them to choose sperm from a donor whose traits they hope to replicate in the child. The prospect of genetic enhancement using the techniques of recombinant DNA manipulation can allow for more precision and wider applications than older approaches such as selective sperm banking.

Knowledge that one carries a gene for a heritable disease can pose a profound dilemma for the individual. An early form of this dilemma arose when carrier screening was the only way to determine whether a couple would pass on a genetic disease to their offspring. A couple then had to decide whether to take the chance that a child would be born with the heritable condition. With the advent of various forms of prenatal diagnosis (amniocentesis, chorionic villus sampling, blood tests), the presence of some genetic diseases in a fetus can be detected. The ethical question in such cases is whether to abort an afflicted fetus. In the case of both carrier screening and prenatal diagnosis, trained genetics counselors have uniformly taken a nondirective approach. The norm in genetics counseling has generally been to provide unbiased information to enable individuals or couples to make an informed decision whether to initiate a pregnancy or to abort a fetus found to have a genetic disease (Lappe 1971, President's Commission for the Study of Ethical Problems 1983).

As the science of genetics yields an increasing amount of information, individuals are faced with making decisions about prophylactic medical interventions. For example, a woman who learns that she carries a gene for an inherited form of breast cancer may contemplate bilateral mastectomy before any clinical signs appear. The epistemological problem posed by such scenarios is a familiar philosophical one: decision making under risk and uncertainty. If the woman decides to undergo a major, disfiguring operation, she does so with the knowledge that she might escape the disease entirely. But if she forgoes the preventive step, she runs the risk of developing a dread disease that may be curable if detected early but that also has a high mortality rate.

The knowledge by individuals or couples that they are at risk for transmitting a genetic disease to offspring is one indication for embarking on the use of reproductive technologies. The couple may elect to use donated sperm or ova. A far more common indication for the use of reproductive technologies, however, is infertility or subfertility on the part of one or both members of a couple. Methods include in vitro fertilization (IVF)fertilizing a human ovum outside the wombthe use of sperm or ova contributed by third parties or the womb of a woman not intended to be the rearing parent (surrogacy); cryopreservation (freezing) of fertilized ova, which are termed preembryos ; and embryo splitting.

Frequently discussed ethical issues include concerns about destruction of the traditional family when third parties are used as gamete donors or surrogates (Macklin 1991); worries about the effect on children who learn that they were born as a result of these techniques; and the opposite worry about harmful effects of struggling to maintain family secrets. Prior to the first IVF birth in 1978, fears were expressed that IVF would produce a higher than normal incidence of birth defects, but scientific evidence gathered over the years has shown this concern to be unwarranted. The objection that being created with the aid of gametes from a third party can harm the interests of children is countered by the metaphysical observation that these are children who would never have existed but for the use of these techniques.

Different religions are opposed to the use of some or all of these reproductive technologies. The Roman Catholic Church has urged prohibition of virtually all forms of assisted reproduction (Congregation for the Doctrine of the Faith 1987). The church's opposition is based on the fact that these techniques separate the procreative and unitive functions of marriage. Some authorities in Orthodox Judaism allow insemination from non-Jewish sperm donors but prohibit donation from Jews, in order to prevent consanguinity; others oppose all third-party donations out of fear of consanguinity and also by analogy with adultery. Islamic law prohibits the use of sperm or eggs from anyone other than the married couple on grounds that the results are similar to adultery (Serour 1992). Since the identity of gamete donors is normally kept confidential, a secular concern is that a brother and sister may unwittingly mate or marry, unaware that they have a genetic parent in common.

Possibly the most intriguing philosophical issues posed by reproductive technologies are those that arise from the newfound ability to separate the genetic from the gestational procreative functions. IVF permits an ovum from one woman to be fertilized and the resulting embryo implanted in a different woman. This creates the entirely novel situation of two different "mothers": the genetic mother, who supplies the egg; and the gestational mother, who undergoes pregnancy and childbirth. Apart from the emotional or other psychological consequences that may result from such arrangements, the separation of the woman's procreative role into two distinct biological functions requires a conceptual decision of whether the individual who performs each function properly deserves the appellation "mother" (Macklin 1991).

A variation on this conceptual theme stems from research that demonstrates the capability of transplanting ovaries from an aborted fetus into an adult woman who lacks ovaries of her own. The woman into whom the ovaries are transplanted is a mother in the traditional sense of one who is pregnant and gives birth to the child. Is it appropriate to construe the aborted fetus as the "genetic mother"? The conceptual oddity of this construal suggests that "mother" is a concept laden with connotations that do not permit its expansion to include aborted fetuses. Although the aborted fetus is without question the source of the genetic material from which the new life was created, it is semantically odd to conclude that the aborted fetus is the genetic mother.

A persistent quandary relates to the status of extracorporeal embryos. The product of IVF is termed a preembryo, partly because of its early developmental stage but also because it is unimplanted. The ability to freeze embryos indefinitely and thaw them for use later poses both conceptual and ethical questions. When disputes arise concerning the ownership of embryos, should the embryos be construed as "people" or as "property" (Annas 1989, Robertson 1990)? Should anyone other than the couple who contributed the gametes have the authority to destroy frozen embryos? If it is permissible to destroy embryos that are not intended for implantation, is it permissible to do experiments on the embryos? Controversy exists over the splitting of embryos, a technique sometimes called cloning (Robertson 1994). One objection holds that such deliberate duplication destroys genetic individuality and thus devalues the uniqueness of each individual.

Genetics and reproductive technologies pose new philosophical questions about the scope and limits of such familiar concepts as disease, individuality, parent, mother, and the family. The importance accorded to human reproduction and lineage throughout history is a reminder that such questions are not merely abstract concerns of philosophers but deeply rooted in the lives of individuals and communities.

See also Abortion; Bioethics; Distant Peoples and Future Generations; Evolutionary Theory; Human Genome Project; Informed Consent.

Bibliography

Annas, G. J. "A French Homunculus in a Tennessee Court." Hastings Center Report 19 (1989): 2022.

Congregation for the Doctrine of the Faith. Instruction on Respect for Human Life in Its Origin and on the Dignity of Procreation. Vatican City, 1987.

Fletcher, J. The Ethics of Genetic Control: Ending Reproductive Roulette. Garden City, NY: Anchor Press, 1974.

Lappe, M. "The Genetic Counselor: Responsible to Whom?" Hastings Center Report 2 (1971): 68.

Macklin, R. "Artificial Means of Reproduction and Our Understanding of the Family." Hastings Center Report 21 (1991): 511.

Milunsky, A., and G. J. Annas, eds. Genetics and the Law III. New York: Plenum Press, 1985.

President's Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research. Screening and Counseling for Genetic Conditions. Washington, DC: President's Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research, 1983.

President's Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research. Splicing Life. Washington, DC: President's Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research, 1982.

Proctor, R. N. Racial Hygiene: Medicine under the Nazis. Cambridge, MA: Harvard University Press, 1988.

Ramsey, P. Fabricated Man: The Ethics of Genetic Control. New Haven, CT: Yale University Press, 1970.

Robertson, J. A. "In the Beginning: The Legal Status of Early Embryos." Virginia Law Review 76 (1990): 437517.

Robertson, J. A. "The Question of Human Cloning." Hasting Center Report 24 (1994): 614.

Serour, G. I. "Medically Assisted Conception: Islamic Views." In Proceedings of the First International Conference on Bioethics in Human Reproduction Research in the Muslim World, edited by G. I. Serour. Cairo, 1992.

Ruth Macklin (1996)

About this article

Genetics and Reproductive Technologies

Updated About encyclopedia.com content Print Article

NEARBY TERMS

Genetics and Reproductive Technologies