Autosomal dominant ataxia disorders
In autosomal dominant ataxia disorders, an individual only needs to inherit one copy of a defective gene in order to develop a disorder. Types include:
- spinocerebellar ataxia (SCA) types 1 through 14
- Machado-Joseph disease (SCA type 3)
- dentatorubral-pallidoluysian atrophy (DRPLA)
- episodic ataxias – symptoms may last from minutes to hours
Autosomal recessive ataxia disorders
In autosomal recessive ataxia disorders, an individual needs to inherit two copies of a defective gene, one from each parent, in order to develop a disorder. Types include:
- Friedrich ataxia – usually begins in first 10-20 years of life, but sometimes begins in adulthood
- ataxia with vitamin E deficiency
- ataxia-telangiectasia
- ataxia of Charlevoix-Saguenay
Common symptoms
Symptoms of ataxia disorders, and when they begin, may be different depending on which specific disorder is present. The symptoms of ataxia often become worse over time. Some common symptoms may be:
- difficulty maintaining balance and walking
- difficulty coordinating movements of hands, arms, and legs
- slurred speech, difficulty eating and swallowing
- double vision (diplopia)
- joint pain (dysarthria)
Diagnosis
Diagnosis of an ataxia disorder is usually suggested by the symptoms the person is experiencing. Tests may be done to exclude other disorders or conditions that may cause ataxia. Genetic blood tests are available for some types of inherited ataxia (such as Friedrich ataxia) to confirm a diagnosis.
Treatment
In general, there are no specific treatments available for most of the inherited ataxia disorders. Symptoms are treated with physical and occupational therapy, assistive devices, and medication for muscle pain or spasms that may occur.
Genetic counseling
It is important for individuals with an inherited ataxia disorder to be aware that they may pass the disorder on to their children. A genetic counselor can provide education about inheritance. Some families affected may choose to test family members to see if they have inherited the gene responsible for the disorder.
Sources:
- "Ataxias and Cerebellar/Spinocerebellar Degeneration Information Page." Disorders. 04 Dec 2006. National Institute of Neurological Disorders and Stroke. 29 Jan 2007 <http://www.ninds.gov/disorders/ataxia/ataxia.htm>.
- "What is Ataxia?" Questions About Ataxia. National Ataxia Foundation. 31 Jan 2007 <http://www.ataxia.org/learn/ataxia-diagnosis.aspx>.
- Subramony, S.H.. "Inherited Ataxias." ACP Medicine Online 07 Jun 2006 29 Jan 2007 <http://www.medscape.com/viewarticle/479286>.
