SMA is a progressive neuromuscular disease.4
SMA is defined as a neuromuscular disease of the central nervous system (CNS) that results in the deterioration of motor function and strength over time, although the rate and severity vary. Watch to learn more about the cause and symptoms of SMA.3-5
Mechanism of disease
Watch the video to learn about the clinical manifestations and cause of SMA.
SMA is caused by a lack of functional SMN protein.4
Two nearly identical genes produce survival motor neuron (SMN) protein.7
People with SMA have a deleted or mutated SMN1 gene and rely on the SMN2 gene to produce functional SMN protein. However, SMN2 can only produce about 10% of the functional protein the motor neurons need to power muscles, resulting in the progressive loss of strength and motor function that all with SMA experience.
Why it’s important to consider treating SMA as soon as possible.
Motor function loss is permanent and can be unpredictable.1,5,8
Because the rate of motor function loss is different for every patient, there is no way to predict when motor function loss will occur or how severe it will be.
Adults with later-onset SMA
are at risk for progression.1,8
Despite apparent plateaus, untreated adults with later-onset SMA will continue to lose muscle strength or function over time.
