what is sma

Spinal muscular atrophy (SMA) is a progressive genetic neuromuscular disease characterized by the degeneration of motor nerve cells in the spinal cord, leading to muscle weakness and atrophy. It primarily affects muscles used for movement, breathing, eating, crawling, and walking by impairing the motor neurons that control these muscles. SMA is caused by mutations in the survival motor neuron gene 1 (SMN1), resulting in low levels of the SMN protein, which is crucial for motor neuron function. Without sufficient SMN protein, motor neurons deteriorate and muscle control is severely affected. SMA has multiple types, classified based on the age of onset and severity of symptoms, ranging from severe forms evident before birth to milder adult-onset forms. Although there is no cure, disease-modifying treatments and supportive care can improve survival and quality of life for those affected.