Spinal muscular atrophy (SMA) is a genetic disorder that affects the nervous system and leads to progressive muscle weakness and atrophy. It is caused by mutations in the survival motor neuron 1 (SMN1) gene, which is responsible for producing a protein essential for motor neuron survival. Without enough of this protein, motor neurons deteriorate, leading to muscle weakness and difficulty with movement, breathing, and swallowing.

There are different types of SMA, ranging from severe forms that appear in infancy (Type 1) to milder, later-onset forms (Type 3 and Type 4). Early diagnosis and intervention can significantly impact disease progression and quality of life.