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GTR Home > Tests > Spinobulbar Musc Atrophy, Kennedy's

Performance Characteristics



  • Entire test performed in-house

Analytical Validity


Accuracy ≥ 99%


Not provided

Assay Limitation(s)


For predictive testing, it is important to first document the presence of a CAG-repeat amplification in the androgen receptor (AR) gene in an affected family member to confirm that molecular expansion is the underlying mechanism of disease in the family. We strongly recommend that patients undergoing predictive testing receive genetic counseling both prior to testing and after results are available. Predictive testing of an asymptomatic child is not recommended. Test results should be interpreted in the context of clinical findings, family history, and other laboratory data. Errors in our interpretation of results may occur if information given is inaccurate or incomplete.. Current evidence suggests that the majority of individuals with spinobulbar muscular atrophy (SBMA) have a CAG-repeat expansion. However, we cannot eliminate the possibility that another type of mutation not detected by our assay is present within the AR gene.

Proficiency Testing (PT)

Is proficiency testing performed for this test? Help
Method used for proficiency testingHelp
Platform PT performed

FDA Regulatory Clearances of the Test

FDA Category Designation
FDA exercises enforcement discretion

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