Invitae C9orf72-related Frontotemporal Dementia and Amyotrophic Lateral Sclerosis Repeat Expansion Test
Use
The Invitae C9orf72-related Frontotemporal Dementia and Amyotrophic Lateral Sclerosis Repeat Expansion Test analyzes hexanucleotide repeat expansions in the C9orf72 gene, the most common hereditary cause of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). This test helps confirm clinical diagnosis, predict disease progression, facilitate early detection, inform family planning and genetic counseling, and promote clinical trial enrollment.
Special Instructions
Ordering this test may require pre-test genetic counseling due to the implications of testing for neurodegenerative disorders with no known cure. Alternative specimen types like saliva, buccal swab, and gDNA are accepted, but blood is preferred.
Limitations
This test cannot determine the exact repeat number beyond 31 repeat units and does not assess methylation status. False negatives may occur due to rare downstream sequence variations. It is not validated for low-level mosaic variants, and results may not reflect repeat size in untested tissues. The analyzed DNA may not represent the constitutional genome in cases of bone marrow transplant, transfusion, or maternal cell contamination.
New York Approved
Methodology
PCR-based (RP-PCR)
Biomarkers
Result Turnaround Time
10-21 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
3mL
Minimum Volume
Not provided
Container
purple-top EDTA tube (K2EDTA or K3EDTA)