Huntington's disease is a degenerative disease of the brain which is inherited as an autosomal dominant trait. This means that only 1 parent needs to have the abnormal gene to pass the disease on and that about 50% of the children will be affected. Symptoms usually start in the 3rd or 4th decade of life but can begin in childhood or as late as retirement age.
The main symptoms are involuntary movements, dementia and psychiatric disturbance. All symptoms worsen over time. Although there is no cure, there are useful treatments for many of the symptoms.
The recent discovery of the abnormal Huntington's disease gene has led to the development of a blood test for making a definitive diagnosis in individuals suspected of having this disease. At risk individuals should receive genetic counseling, and neurological and psychiatric evaluation as part of the process.