SPINAL CEREBRAL ATAXIA TYPE - 3, EDTA BLOOD

What is Spinal Cerebellar Ataxia Type 3 (SCA3) test?

Spinal Cerebellar Ataxia Type 3 (SCA3), also known as Machado-Joseph Disease (MJD), is a rare hereditary neurodegenerative disorder caused by a genetic mutation (CAG trinucleotide repeat expansion in the ATXN3 gene). This genetic test detects the presence of expanded CAG repeats in the ATXN3 gene using a blood sample.

Why consider Spinal Cerebellar Ataxia Type 3 (SCA3) test?

• Diagnosis of SCA3 in individuals with signs of ataxia (loss of coordination), especially if there's a family history.
• Confirming a suspected clinical diagnosis of SCA3 or ruling out other forms of ataxia.
• Prenatal or pre-symptomatic testing (in special cases, with counseling).
• Differential diagnosis — to distinguish SCA3 from other neurodegenerative disorders (e.g., Parkinson’s, MS, ALS).

Who should get tested for Spinal Cerebellar Ataxia Type 3 (SCA3) test?

You may consider the test if:

• You or a family member has symptoms such as:
• Unsteady gait or balance problems
• Difficulty with speech or swallowing
• Muscle stiffness or twitching
• Vision changes or eye movement abnormalities
• There is a family history of ataxia or related neurological disorders.
• A neurologist suspects SCA3 based on clinical findings and imaging.
• You're undergoing genetic counseling or planning a family and there is known SCA3 in the family.

More Information

OTHER NAMES: Spinocerebellar Ataxia Type 3 (SCA3). Machado‑Joseph disease (MJD). ATXN3 CAG repeat expansion testing; Ataxin‑3 gene test. SCA3 Genetic Test, Machado-Joseph Disease DNA Test, ATXN3 Gene Testing, SCA Panel

Spinal Cerebellar Ataxia Type 3 (SCA3) is a hereditary neurodegenerative disorder that primarily affects the brain and spinal cord, leading to progressive problems with movement and coordination. This mutation causes toxic accumulation of abnormal proteins in nerve cells, leading to cell death in areas that control movement, balance, and coordination.

It is the most common type of autosomal dominant spinocerebellar ataxias worldwide.