Spinal Muscular Atrophy (SMA), Diagnostic
Use
Spinal Muscular Atrophy (SMA), Diagnostic assesses SMN1 and SMN2 copy number to diagnose SMA, which primarily results from deletion of exon 7 of SMN1—responsible for ~95% of cases. It distinguishes affected individuals from carriers and informs clinical diagnosis in patients with SMA-like phenotype.
Special Instructions
This germline genetic test requires physician attestation of informed consent if the ordering medical facility is located in AK, DE, FL, GA, IA, MA, MN, NV, NJ, NY, OR, SD, VT, or if the test is performed in MA. Do not freeze whole blood specimens; transport at room temperature.
Limitations
This assay does not detect sequence variants or complex rearrangements in SMN1 beyond copy number changes; it does not assess risk for 2+0 carrier status in fetal testing. Not indicated for prenatal chorionic villi or fetal specimens.
Methodology
PCR-based (PCR)
Biomarkers
Result Turnaround Time
Not provided.
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
4 mL
Minimum Volume
2 mL
Container
EDTA (lavender‑top), ACD (yellow‑top), 3.2% sodium citrate (light blue‑top), EDTA (pink‑top), or sodium heparin (green‑top) tube
Collection Instructions
Collect whole blood in any of the specified anticoagulant tubes. Do not freeze. Transport at room temperature.
Storage Instructions
Room temperature transport; do not freeze.
Causes for Rejection
Frozen specimen; chorionic villi and fetal specimens unacceptable.
Other tests from different labs that may be relevant