Huntington disease is a rare inherited (genetic) condition that causes parts of the brain to break down and lose some normal functions (degeneration). It is also called Huntington chorea.

Symptoms of the disease usually develop after age 40 and include rapid, jerky movements (twitches in the face and jerks of the arms) that cannot be controlled (chorea) and the gradual loss of mental abilities (dementia), leading to personality changes, behaviour problems, and memory loss.

There is no known cure for the disease. Treatment with medicines may help control the involuntary movements.