Spinal Muscular Atrophy With Respiratory Distress (SMARD)
Also known as: distal spinal muscular atrophy (DSMA1), distal hereditary motor neuronopathy type VI (dHMN6 or HMN6)
Gene: IGHMBP2
Protein: immunoglobulin mu-binding protein 2
Clinical Characteristics
- Sudden onset of respiratory symptoms:
- Stridor/weak cry
- Diaphragmatic paralysis within first year of life
- Muscle weakness:
- Initially distal, progressing to generalized
- Intrauterine growth retardation
- Premature birth
- Foot deformities
- Autonomic nervous system dysfunction
- Seizures
- Phenotypic variability between and within families
Inheritance pattern: Autosomal recessive
What Can Be Learned From This Test
Testing is performed by sequencing all exons and partial intronic regions of IGHMBP2. This will detect point mutations, small deletions and small insertions. It will not detect a partial or whole gene deletion or duplication.
Sample Requirements
Draw 2ml–4ml of blood in EDTA/purple-top tube (minimum of 1ml–2ml for infants).
Turnaround time: 10-14 business days
CPT Codes and Cost
Full Gene Sequencing
- Code: 81479
- Cost: $1,500
Known Variant Testing
- Code: 81479
- Cost: $225