Predictive genetic testing: ethical, legal, and social implications.

• Author: Allen, Bill

IMAGINE VISITING your physician for a routine physical, and he or she recommends that you have a new genetic test run on a small sample of your blood. The doctor informs you that it will indicate your chances for developing certain diseases at some point in the future, including breast and colon cancer, heart disease, diabetes, and Alzheimer's. The physician also assures you that you have no physical symptoms of any of these conditions and, even if the test indicates the likelihood of a disease, you may not have any symptoms for years, if ever. It is explained that, if the results indicate a probability of increased risk for one or more of these diseases, there are no preventive treatments. The doctor notes that you might be able to reduce the risk by lifestyle changes, such as controlled diet and smoking cessation. If the condition does manifest itself, some treatment options may be available, but they are limited and frequently invasive.

Although such a test might be a major advance for predicting future health risks and preventive medicine, it also would raise a host of complex social and ethical issues for the patient and physician. For example: Would the anxiety of living with the likelihood of one or more specific, chronic, debilitating diseases create psychological burdens that outweigh the therapeutic potential of lifestyle changes or earlier treatment due to increased vigilance? If no effective interventions are known, would it be better to live without knowing your genetic fate, or to understand the chances of disease in order to make life plans accordingly? Would you tell your spouse about the prospect of genetically influenced disease? Your fiancee? Would they have a right to know? Would it be unethical to have children to whom you might pass along the risk of the genetic susceptibility? Would you tell your employer or a prospective employer? Would you notify your insurance company? Would you apply for more life or health insurance? Would your employer and insurance company have a right to learn the test results and use them in employment and employee benefit decisions?

Predictive genetic tests are not merely science fiction; neither are they projections of a remote time in the future. A few already are in use, while others are in the development stage and will be available soon. These powerful new medical tools soon will help physicians make early predictions of potential chronic health problems and, perhaps, allow early intervention. In order to minimize the quandaries that may accompany such advances, the social and ethical consequences of genetic information with predictive significance must be anticipated.

Begun in 1990 by the National Institutes of Health and the U.S. Department of Energy, the Human Genome Initiative (HGI) is a 15-year coordinated research endeavor. The goal is to locate and identify the functions of the 50,000-100,000 genes that determine human hereditary characteristics, with a special focus on those that affect health and longevity.

Even when a genetic "map" is complete and the sequence of human deoxyribonucleic acid (DNA) has been deciphered, it will take decades of additional research to understand the functions of genes more fully. Yet, the impact of what is discovered in the next dozen years likely will be useful enough to warrant expert projections that individuals will carry their own distinctive, complete genetic codes on the 21st-century equivalent of a compact disc. The U.S. military already is using such information as a more definitive means of identification than dog tags or dental records, and some hospitals have begun to use genetic identification of newborns to prevent the types of mix-ups at birth that resulted in the Kimberly Mays case.

Although the project is in its early stages, the medical and social impact of such genetic research is being felt. So far, most of the advances have focused on 4,000 identified disorders that require an...