Spinocerebellar Ataxia Type 17

What is Spinocerebellar Ataxia Type 17 (SCA17) test?

Spinocerebellar Ataxia Type 17 (SCA17) is a rare inherited neurodegenerative disorder caused by a CAG/CAA trinucleotide repeat expansion in the TBP gene (TATA-box binding protein gene). The SCA17 test involves analyzing a blood sample (collected in an EDTA tube) to detect this repeat expansion, confirming or ruling out the diagnosis of SCA17.

Why consider Spinocerebellar Ataxia Type 17 (SCA17) test?

This test is recommended when:

• An individual exhibits symptoms of progressive ataxia (loss of balance and coordination)
• Symptoms include cognitive decline, psychiatric symptoms, and movement disorders (which can mimic Huntington’s disease)
• There is a family history of spinocerebellar ataxia or similar neurological disorders
• To differentiate SCA17 from other SCAs or neurodegenerative diseases
• For predictive testing in at-risk family members

Who should get tested for Spinocerebellar Ataxia Type 17 (SCA17) test?

• Patients with progressive gait and limb ataxia, cognitive impairment or dementia, psychiatric symptoms such as depression or psychosis and movement abnormalities such as chorea or dystonia.
• Individuals with a family history of SCA17 or related disorders
• People with unclear diagnosis of other neurodegenerative diseases resembling Huntington’s disease or SCAs

More Information

OTHER NAMES: SCA17 Genetic Test, TBP Repeat Expansion Test, Spinocerebellar Ataxia Type 17 DNA Analysis, Hereditary Ataxia Type 17 Test, Autosomal Dominant Cerebellar Ataxia Type 17

Spinocerebellar Ataxia Type 17 (SCA17) is a rare, inherited neurodegenerative disorder caused by an abnormal expansion of CAG/CAA trinucleotide repeats in the TBP gene (TATA-box binding protein gene). This gene is important for regulating the expression of many other genes. SCA17 affects movement, cognition, and behavior due to progressive degeneration of the cerebellum and other parts of the brain.