Huntington disease (HD) is an inherited brain disorder: It is named after the doctor who first descibed in 1872, George Huntington, and it used to be called Huntington's chorea.

HD causes cells in specific parts of the brain to die: the caudate, the putamen, and, as the disease progresses, the cerebral cortex. The caudate and putamen have connections to many other areas of the brain, and help to control body movement, emotions, thinking, behavior, and perception of the world.

As the brain cells die, people with Huntington's become less able to control movements, recall recent events, make decisions, and control emotions. The disease leads to incapacitation and, eventually, death.