Huntington´s disease is a hereditary genetic disorder meaning that each child of a parent that has been diagnosed with HD has a 50% chance of inheriting the disease and are said to be at-risk.  Males and females have the same risk of inheriting the disease and HD occurs in all races.  Carriers of the HD gene will eventually develop Huntington´s Disease unless they die of some other cause before the onset of symptoms.

HD occurs in approximately 1 in 10 000 people in most “western” countries. In other countries the prevalence may be much lower, although not much data about HD is available in African countries for example.