Francisco Lopera (left) and Ken Kosik (middle) ride through Colombia to visit members of the largest known family with a genetic mutation for Alzheimer’s. In the back is Lucia Madrigal, a longtime member of Lopera’s research team.

Francisco Lopera (left) and Ken Kosik (middle) ride through Colombia to visit members of the largest known family with a genetic mutation for Alzheimer’s. In the back is Lucia Madrigal, a longtime member of Lopera’s research team.