Spinal Muscular Atrophy (SMN1/SMN2 Dosage)
Collection Requirements
Source: blood
Container: EDTA lavender
Volume:
- Preferred: 3 mL in vacutainer
- Minimum: 1 mL in vacutainer
Source: buccal/saliva
Container: OraCollect Kit
Source: amniotic fluid
Container: minimum 2 sterile centrifuge tubes
Volume: 20 mL amniotic fluid
Source: chorionic villi
Container: sterile cup or tube with sterile
transport medium
Volume: optimal sample is >50 mg of chorionic
villi
Source: tissue
Container: sterile cup with sterile transport
medium
Volume: 20 mg tissue
Source: tissue, fresh frozen
Container: sterile cup
Volume: 20 mg tissue
Special Instructions
Contact Genetics for transport medium
Turn Around Time
7 days
Availability
Routine
Lab Processing Instructions
Specimen: whole blood
Room temperature or refrigerate
Specimen: buccal/saliva, amniotic fluid, chorionic
villi, or tissue in transport medium
Room temperature
Specimen: tissue, fresh frozen
Freeze
Performing Laboratory
Adele Hall
Adele Hall Lab Section
Molecular Genetics
Instrumentation/Methodology
Multiplex ligation dependent probe amplifaction (MLPA) is used to detect copy number changes in the SMN1 and SMN2 genes
Additional Information
Spinal muscular atrophy (SMA) is characterized by muscle weakness and atrophy resulting from progressive degeneration and loss of the anterior horn cells in the spinal cord (i.e., lower motor neurons) and the brain stem nuclei. The onset of weakness ranges from before birth to adolescence or young adulthood. The weakness is symmetric, proximal > distal, and progressive.
Reference Ranges
See interpretive report
CPT
81329