If you have recently been made aware that SMA runs in your family, or have noticed symptoms that might indicate SMA in you or your child, speak to your doctor for more information about testing. Symptoms to keep an eye out for include:
- Muscle weakness and/or low muscle tone in the arms, legs, torso, shoulders, and/or hips — children may seem ‘floppy’
- Poor head control
- Difficulty breathing, swallowing or sucking
- Weak cry or cough
- Cannot sit or roll independently (0–6 months)
- Cannot stand or walk (7–18 months) or loss of the ability to walk (18+ months)
- Scoliosis (a curved spine)
- Tremors or twitching
If SMA is suspected, a blood test will be requested, which will look for the presence or absence of the SMN1 gene. If the SMN1 gene is absent, SMA can be diagnosed.
If the gene is present, other diagnostic tests will take place to rule out rare forms of SMA caused by changes to different genes, and other neuromuscular conditions. In two to five per cent of patients with SMA, the SMN1 gene is not missing, just inactive. Testing for this is more complicated and may take some time.
The healthcare professional simply needs to take a blood sample. Some discomfort may be felt as part of standard blood test procedures.
From 1 November 2023, genetic carrier screening for SMA, Cystic Fibrosis and Fragile X syndrome was made freely available through Medicare to Australians who are pregnant or planning a pregnancy and their reproductive partner, helping them to make more informed reproductive choices. For those people who do not meet these Medicare criteria, testing is available at a cost. Speak to your testing provider for further information.