For genetic testing related to breast cancer and Huntington’s disease, such investigations are likely to be initiated in an asymptomatic patient with a relevant family history. Testing for Down syndrome is routine for pregnant women over the age of 35. With the advent of maternal serum markers, aggressive obstetricians may recommend this type of testing to all their patients.

The right to privacy, closely related to the bioethical principle of autonomy, is the main concern in genetic testing. With whom will the results be shared? With BRCA mutation testing, a mother or daughter can find out that she is a carrier of BRCA1 or BRCA2. Knowledge of this result can be valuable to the daughter or the mother, respectively. But the mother, for example, may want to keep the results private. She does not want her husband to know and is afraid that her daughter may share the news not only with family but also with friends.

In some cases, the mother and daughter share a family doctor. Is that doctor obligated to communicate critical information to the daughter, even though such action will violate the mother’s right to privacy? The principles of autonomy and beneficence are in conflict in such a scenario. Does the mother have an obligation to communicate the information to her daughter? Their personal autonomy is at odds with their moral obligation to care for their children.

Similarly, a father, whose own mother had Huntington’s disease, chooses to get tested when he is 40 years old. You learn that you have an excessive number of CAG repeats in the HTT gene on the short arm of chromosome 4. You will undoubtedly develop Huntington’s disease. Are you obliged to tell your children? Is your doctor obliged to share the information? Once again, the relevant bioethical principles are in conflict.

An expectant mother wants to learn all she can about the potential health of her future baby. Your fetus carries an HTT abnormality that suggests Huntington’s disease started after age 40. She took the test herself and found out that she is not a carrier of the gene. As a result of this process, you have obtained private medical information about your partner. You will develop Huntington’s disease. Are you obliged to share this information? There are implications for your parents and your children from a previous marriage.

Also, should I abort the fetus? If you choose to have this child, are you imposing an unfair burden on society? Who will bear the costs of caring for your child after the illness occurs? Could these resources have better uses elsewhere? The bioethical principles of justice and autonomy are in conflict.

Would you act irresponsibly if you chose to have more children with your partner? Each child would have a 50% chance of developing Huntington’s disease. Such actions would be ethical, since decades of healthy existence would be preferable to never having been born.

With prenatal trisomy 21 screening, what are the doctor’s duties? Should I recommend termination of pregnancy, or should I also point out the many people with Down syndrome who are leading fruitful lives? On the other hand, are these prenatal tests for all pregnant women an appropriate use of scarce resources?

These are some of the many ethical issues that people and doctors face on a daily basis. Many more will emerge as technology continues to advance. The fields of bioethics and jurisprudence must be proactive and consider these issues deeply before future scientific and technological developments.

1 See, for example, Robertson JA: Children of Choice. Freedom and new reproductive technologies. Princeton, NJ, Princeton University Press, 1994