Ready or not, medical practice is changing. Advances in the field of genomics—the study of how our DNA is constructed and functions—have made it easier for physicians to diagnose, treat, and even predict today's many pressing health concerns. With the emergence of genomic sequencing and DNA analysis, this is an exciting moment in science, medicine, and personal health.

But it's also an uncertain time, one fraught with understandable and uncomfortable questions:

In Genomic Messages, George Annas, j.d., m.p.h., and Sherman Elias, M.D., a health lawyer/bioethicist and an obstetrician-gynecologist/geneticist,...