In the late 1970s, an archaeologist exploring the Colombian Andes for tombs and relics of past civilizations met an elderly farmer who told him of a field where, as a child, he had been forbidden to play. The field was dangerous, his mother told him, because of the two-headed monster that lived there. The archaeologist and his team excavated the site—buried in the field, they found the full-size statue of a man with two heads.

Who made the statue and how it came to be buried there remained mysteries. Yet somehow, as in a game of Telephone, knowledge of the statue had passed down through the generations. With each telling, the story changed. DNA similarly passes from generation to generation, but it doesn’t always come out right. Ideas move through time, and they change with the times. We inherit many things from our ancestors, be they blue eyes and brown hair, notions of right and wrong, or just habits and ways of being. In this issue of Yale Medicine, we look at the ways in which these inheritances emerge intact—or sometimes not.

This issue’s feature articles explore what DNA reveals about human history, how med school traditions endure or fall by the wayside, and how one family copes with an inherited disease.