Paul R. Billings, Ruth Hubbard, and Stuart A. Newman

About the author: Paul R. Billings is a clinical genetics expert and cofounder of GeneSage, a company that provides genetic services to consumers and health professionals. Ruth Hubbard is professor emerita of biology at Harvard University and author of Exploding the Gene Myth. Stuart A. Newman is a professor of cell biology and anatomy at New York Medical College and coeditor of Beyond the Gene in Developmental and Evolutionary Biology.

In germ line gene therapy, human germ cells would be modified, resulting in inheritable changes in DNA. This has not yet been achieved, but scientific research suggests that the obstacles in conducting the procedure may someday be overcome. However, germ line manipulation must be vigorously opposed for several reasons. It may...