As far-reaching biomedical technologies emerge from research labs, Americans are beginning to grapple not only with how these breakthroughs might enhance people’s health and abilities, but also with the profound ethical and moral questions the discoveries raise.

How much change in the physical makeup of humans is possible and acceptable? When does enhancement of human abilities cross a line by giving some people unfair advantages over others? What oversight and regulation of body- and brain-changing procedures is necessary? And how should the government or insurance marketplaces respond to the availability of life-altering technologies?