To find a treatment, researchers first have to find a cause, a mutation or malfunction in one or more genes. The cause might be a genetic change that inhibits the normal functioning of the "polite" and "common sense" regions of the brain. But no previous research has been done on rude cell phone behavior, so scientists have very little idea of what genes may be malfunctioning to cause the rude behavior. The mutation they are looking for could literally be any one of 3.1 billion base pairs in the human genome. How do they know where to start?