Genetic Testing
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"The scientific community cannot shoulder the whole burden of bringing ethics to bear. Catholic clergy and laity must become knowledgeable about emerging biotechnologies if they are to help people make the critical decisions they will inevitably face ."


U.S. Bishops




Critical Decisions:
Genetic Testing and its Implications

The Catholic Bishops of the United States believe that, despite occasional tensions and disagreements, there can be no irreconcilable conflict between religion and science.

This statement is the second in a series designed to show how religion and science can offer complementary insights on complex topics like the emerging biotechnologies. It is offered to people of science and of faith, indeed, to all those concerned with the moral implications of humanity’s new knowledge and power.

National Conference of Catholic Bishops
Committee on Science and Human Values


  • Mrs. Smith undergoes prenatal testing and discovers that her unborn child has a large defect in the closure of the brain or spinal cord.


  • Optimum Insurance asks all applicants for individual health care policies to undergo testing for the gene that predisposes to



  • Optimum Airlines alerts its employees that testing for sickle-cell trait is now available.


  • Optimum Pharmaceuticals develops a therapy for depression and offers a test to detect the relevant genetic profile.


  • The Supreme Court allows testing to identify those at increased risk for Alzheimer’s disease, on the grounds that people have a

    right to this information in planning their future.


  • The state of Maryland denies a marriage license to two people with mild mental retardation; testing shows they may pass severe 

               retardation to their children, raising health costs.

These situations, though fictional, are not fanciful. Several are present reality, and the rest could happen in a decade or two. Genetic testing—and genetic counseling on how to deal with the results of tests—will certainly grow at a rapid rate, creating a burgeoning challenge for pastors and Catholic health care providers. Obviously, the Church cannot offer a credible opinion on the quality or reliability of these tests; that is the province of the scientific and medical communities. However, genetic testing raises and will continue to raise moral issues for the individual, for the family, for racial or ethnic groups, and for society as a whole. The Church has a responsibility to offer insights based on its venerable tradition and current experience, not only to inform consciences and assist in the formation of wise public policy, but also to keep tradition vital.

Most often genetic tests show no disease, relieving anxiety. Moreover, the Catholic Church welcomes testing when it functions as an extension of sound medical practice. Catholics have served the sick for many centuries, and the Church is one of the major providers of health care in the world; naturally, it applauds every medical advance that promises healing without violating moral law. Pope John Paul II told the World Medical Association in 1983:

A strictly therapeutic intervention whose explicit objective is the healing of various maladies such as those stemming from chromosomal defects will, in principle, be considered desirable, provided it is directed to the true promotion of the personal well-being of the individual. . . .Such an intervention would indeed fall within the logic of the Christian moral tradition.

Genetic testing can assist sound decision-making in a wide range of situations. It is most commonly employed to detect problems with newborns. Moreover, millions of Americans are hospitalized every year because of hereditary disease and congenital defects. To the extent that genetic testing sets the stage for a cure or effective therapy, it is a blessing.

Testing has legitimate uses even in the delicate arena of human reproduction. Young couples considering marriage may want to know whether one or both partners carry a gene associated with mental retardation, cystic fibrosis, breast cancer, or some other heritable condition. While such testing carries risk, it can be considered an act of prudence, whether the couple subsequently decides to marry or not.

More and more frequently, expectant mothers are undergoing amniocentesis, chorionic villus sampling, and other tests to detect genetic anomalies in their unborn children. The most detailed Catholic teaching on this and related subjects appears in a 1987 statement from the Vatican Congregation for the Doctrine of the Faith called The Gift of Life (Donum Vitae). It asks: “Is prenatal diagnosis morally licit? If prenatal diagnosis respects the life and integrity of the embryo and the human fetus and is directed toward its safeguarding or healing as an individual, then the answer is affirmative” (sec. I, no. 2). The Holy Father builds on this declaration in his recent encyclical The Gospel of Life (Evangelium Vitae), holding that prenatal diagnostic techniques are morally permissible “when they do not involve disproportionate risks for the child and the mother, and are meant to make possible early therapy or even to favor a serene and informed acceptance of the child not yet born” (no. 63).

However, some prenatal testing poses significant risks to the unborn child, especially when performed on embryos before selection for implantation in the womb. Disturbing test results can also tempt individuals to make decisions not in accord with sound morality. The Holy Father goes on to note:

But since the possibilities of prenatal therapy are today still limited, it not infrequently happens that these techniques are used with a eugenic intention which accepts selective abortion in order to prevent the birth of children affected by various types of anomalies. Such an attitude is shameful and utterly reprehensible, since it presumes to measure the value of a human life only within the parameters of “normality” and physical well-being, thus opening the way to legitimizing infanticide and euthanasia. (no. 63)

The Church condemns and will never cease condemning the taking of innocent unborn life, surely the saddest aggression of our violent time.

Other uses of genetic testing, though perhaps not clearly sinful, invite serious moral reflection. Current therapies, by and large, manipulate a single gene or gene product. Science has not identified the multiple genes that may help determine high intelligence, a strong heart, immunity to cancer, a sunny personality, forcefulness of character, or other complex traits. Within ten years or less, however, the Human Genome Initiative will have decoded the physical structure of all 100,000 of our genes. Decades, perhaps centuries, of research and experiment may be needed to develop sophisticated technology from this data. Even then, some traits may turn out to have no significant genetic component, while others may spring from so complex a combination of genes, environment, and experience that they remain beyond the reach of empirical analysis.

Nevertheless, the rate of discovery for genes that cause disease or influence physical and mental traits is accelerating rapidly. Within one or two generations, human beings may be able both to change significantly an individual’s genetic makeup through somatic cell therapy and to affect heredity through germline therapy. As time passes, we will learn more about our amazing diversity and our uniqueness. Unfortunately, we will also have the capacity to make finer distinctions among people and to discriminate accordingly. A predisposition to colon cancer is already detectable. If someone tests positive, should this information be available to insurance companies, whose financial success depends on minimizing risk? Potential employers? Potential marriage partners? What if the existence of a gene predisposing to homosexuality is confirmed? Who should have access to test results? These simple examples illustrate the enormous potential for abuse.

The Church’s knowledge of the human heart springs from 2,000 years of moral reflection based ultimately on divine revelation. However, Catholic theology and the Catholic moral tradition mostly predate the development of genetic technologies, which offer new challenges. In an address to the Pontifical Academy for Life in November 1995, Pope John Paul II said:

Indeed, the biomedical sciences are currently experiencing a period of rapid and marvelous growth, especially with regard to new discoveries in the areas of genetics. . . . But if scientific research is to be directed toward respect for personal dignity and support of human life, its scientific validity according to the rules of each discipline is not enough. It must also qualify positively from the ethical point of view, and this presupposes that from the outset it endeavors to promote the true good of human beings as individuals and as a community. This happens when efforts are made to eliminate the causes of disease by putting real prevention into practice, or whenever more effective therapies are sought for the treatment of serious illnesses.

Clearly, the scientific community cannot shoulder the whole burden of bringing ethics to bear. Catholic clergy and laity must become knowledgeable about emerging biotechnologies if they are to help people make the critical decisions they will inevitably face. Both the Church and the scientific community, we believe, can benefit from the effort to harmonize scientific advance with religious insight. Genetic testing is an important tool, but many will suffer if wisdom and sound morality do not guide its use.

Also of Interest

Science and the Catholic Church
The first in a series designed to show how science and religion can offer complementary insights on complex topics like the emerging biotechnologies. The series is offered to people of science and of faith, to all those concerned with the moral implications of humanity's new knowledge and power. From the U.S. bishops' Committee on Science and Human Values.
No. 085-0, brochure

Ethical and Religious Directives for Catholic Health Care Services
Reaffirms the ethical standards of behavior in health care that flow from the Church’s teaching about the dignity of the human person. Provides guidance and direction on moral issues that Catholic health care providers face today. From the U.S. bishops.
No. 029-X, 28 pp.
New Binder Edition: No. 5-034, 16 pp.

To order these resources or to obtain a catalog of other USCC titles, call toll-free 800-235-8722. In the Washington metropolitan area or from outside the United States, call 202-722-8716. For other titles on science and the Church, visit the Science page of the Publishing and Promotion Services' catalog.

Committee on Science & Human Values
United States Conference of Catholic Bishops
3211 4th Street, N.E., Washington, DC 20017-1194 (202) 541-3000