Huntington's disease is a fatal genetic brain disorder. Anyone with a parent with Huntington's has a 50 percent chance of inheriting the disease.
In about 1 to 3 percent of cases, no history of the disease can be found in other family members.
Genetic testing can identify who will acquire Huntington's.
Experts recommend that individuals considering any kind of genetic testing work with a major medical center and a certified genetic counselor.
The age when symptoms develop and rate of progression vary from person to person. Symptoms include:
Involuntary movements such as twitches and muscle spasms.
Problems with balance and coordination.
Personality changes such as irritability, depression and mood swings.
Trouble with memory, concentration or making decisions.
Treatments are available that can help to some extent with motor and mood symptoms, but they do not stop the neurodegeneration.
Huntington's disease is caused by mutations in the gene that encodes a protein called huntingtin. These mutations cause the huntingtin to take on an abnormal shape and form accumulations in the brain that destroy nerve cells.