Spinal Muscular Atrophy

Spinal Muscular Atrophy (SMA) is a genetic disorder characterized by the loss of motor neurons in the spinal cord and the part of the brain that connects to the spinal cord (brainstem), leading to muscle wasting and weakness. This condition is caused by a mutation in the survival motor neuron 1 (SMN1) gene, which is responsible for the production of the SMN protein, necessary for the maintenance of motor neurons. The severity of SMA varies, with Type I being the most severe form presenting in infancy, while Type IV manifests in adulthood with milder symptoms. SMA affects individuals regardless of sex or ethnicity and is inherited in an autosomal recessive pattern, meaning that both copies of the gene in each cell have mutations.

The symptoms of SMA are primarily related to muscle function and include muscle weakness, hypotonia (reduced muscle tone), and difficulties with activities such as crawling, walking, sitting up, and controlling head movement. In severe cases, respiratory muscles are affected, leading to breathing difficulties. Diagnosed through genetic testing, SMA management focuses on supportive care that may include physical therapy, respiratory support, nutritional support, and in some cases, medications such as nusinersen or gene therapy to increase SMN protein production. Research continues to evolve in targeting this disease, improving outcomes and the quality of life for affected individuals.