What are the other Names for this Condition? (Also known as/Synonyms)

• Autosomal Recessive Cerebellar Ataxia Type 2 (ARCA2)
• Autosomal Recessive Spinocerebellar Ataxia due to Coenzyme Q10 Deficiency
• SCAR9 (Spinocerebellar Ataxia, Autosomal Recessive, Type 9)

What is Autosomal Recessive Spinocerebellar Ataxia 9? (Definition/Background Information)

• Autosomal Recessive Spinocerebellar Ataxia 9, also known as Autosomal Recessive Spinocerebellar Ataxia due to Ubiquinone Deficiency, is characterized by childhood-onset progressive ataxia and cerebellar atrophy
• Exercise intolerance with elevated lactate levels and mild intellectual deficit may also be present
• The prevalence of Autosomal Recessive Spinocerebellar Ataxia 9 is unknown
• The syndrome is transmitted as an autosomal recessive trait

(Source: Autosomal recessive spinocerebellar ataxia due to ubiquinone deficiency; Orphanet, National Institute of Health and Medical Research (INSERM), Paris.)

Who gets Autosomal Recessive Spinocerebellar Ataxia 9? (Age and Sex Distribution)

• Autosomal Recessive Spinocerebellar Ataxia 9 is a rare congenital disorder. The presentation of symptoms may occur in childhood
• Both males and females may be affected
• Worldwide, individuals of all racial and ethnic groups may be affected

What are the Risk Factors for Autosomal Recessive Spinocerebellar Ataxia 9? (Predisposing Factors)

• A positive family history may be an important risk factor, since Autosomal Recessive Spinocerebellar Ataxia 9 can be inherited
• Currently, no other risk factors have been clearly identified for the disorder

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Autosomal Recessive Spinocerebellar Ataxia 9? (Etiology)

• Autosomal Recessive Spinocerebellar Ataxia 9 is caused by ubiquinone deficiency
• Mutations in the ADCK3/CABC1 gene have been detected in affected individuals. This gene is known to play a role in ubiquinone biosynthesis in yeast
• The syndrome is transmitted as an autosomal recessive trait

(Source: Autosomal recessive spinocerebellar ataxia due to ubiquinone deficiency; Orphanet, National Institute of Health and Medical Research (INSERM), Paris.)

Autosomal recessive: Autosomal recessive conditions are traits or disorders that occur when two copies of an abnormal gene have been inherited on a non-sex chromosome. If both parents have an autosomal recessive condition, there is a 100% likelihood of passing on the mutated genes to their children. If, however, only one mutant copy of the gene is inherited, the individual will be a carrier of the condition, but will not be present with any symptoms. Children born to two carriers, have a 25% chance of being homozygous dominant (unaffected), a 50% chance of being heterozygous (carrier), and a 25% chance of being homozygous recessive (affected).

What are the Signs and Symptoms of Autosomal Recessive Spinocerebellar Ataxia 9?

The signs and symptoms of Autosomal Recessive Spinocerebellar Ataxia 9 may vary in type and severity among the affected individuals. The signs and symptoms may include:

• Progressive ataxia (childhood-onset)
• Cerebellar atrophy, leading to unsteady gait
• Psychomotor retardation
• Strabismus
• Exercise intolerance with elevated lactate levels (in serum and cerebrospinal fluid)
• Developmental delay
• Mild intellectual deficit 
• Tremors
• Seizures

How is Autosomal Recessive Spinocerebellar Ataxia 9 Diagnosed?

Autosomal Recessive Spinocerebellar Ataxia 9 is diagnosed on the basis of the following information:

• Complete physical examination
• Thorough medical history evaluation
• Assessment of signs and symptoms
• Laboratory tests
• Imaging studies
• Biopsy studies, if necessary

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Autosomal Recessive Spinocerebellar Ataxia 9?

The complications of Autosomal Recessive Spinocerebellar Ataxia 9 may include:

• Risk of falls due to cerebellar atrophy and seizures; thus, risk of fall injuries
• Inability to walk unassisted, due to progressive ataxia

Complications may occur with or without treatment, and in some cases, due to treatment also.

How is Autosomal Recessive Spinocerebellar Ataxia 9Treated?

There is no cure for Autosomal Recessive Spinocerebellar Ataxia 9, since it is a genetic condition. The treatment is usually given to manage the signs and symptoms and any complication that develops.

How can Autosomal Recessive Spinocerebellar Ataxia 9 be Prevented?

Autosomal Recessive Spinocerebellar Ataxia 9 may not be preventable, since it is a genetic disorder.

• Genetic testing of the expecting parents (and related family members) and prenatal diagnosis (molecular testing of the fetus during pregnancy) may help in understanding the risks better during pregnancy
• If there is a family history of the condition, then genetic counseling will help assess risks, before planning for a child
• Active research is currently being performed to explore the possibilities for treatment and prevention of inherited and acquired genetic disorders
• Regular medical screening at periodic intervals with tests and physical examinations are recommended

What is the Prognosis of Autosomal Recessive Spinocerebellar Ataxia 9? (Outcomes/Resolutions)

• The prognosis of Autosomal Recessive Spinocerebellar Ataxia 9 is dependent upon the severity of the signs and symptoms and associated complications, if any
• Individuals with mild conditions have better prognosis than those with severe symptoms and complications
• Typically, the prognosis may be assessed on a case-by-case basis

Additional and Relevant Useful Information for Autosomal Recessive Spinocerebellar Ataxia 9:

Autosomal Recessive Spinocerebellar Ataxia 9 is also known by the following names: 

• Autosomal Recessive Spinocerebellar Ataxia due to Ubiquinone Deficiency
• Autosomal Recessive Spinocerebellar Ataxia Type 9

The following DoveMed website link is a useful resource for additional information:

http://www.dovemed.com/diseases-conditions/rare-disorders/