SMA, or spinal muscular atrophy, is an autosomal recessive disease caused by degeneration of the anterior horn cells of the spinal cord.SMA can be present from birth or not until adulthood, with symmetrical proximal muscle weakness and atrophy at the onset of the disease.Pediatric SMA can result in death due to respiratory muscle weakness, inhalation pneumonia and infection. Spinal muscular atrophy is caused by autosomal recessive inheritance of a deletion or mutation in the SMN1 gene on 5q13. A mutation in the five-base locus of the SMN1 gene causes exon 7 of the gene to be “skipped” during gene transcription, coding for an unstable and rapidly degradable truncated protein that replaces the original full-length protein. The full-length protein is a protein that is stably expressed at high levels in motor neurons, and the reduction in full-length protein due to the SMN1 mutation leads to the degeneration and death of motor neurons, resulting in the development of SMA. There is currently no cure for SMA and it can only be prevented through prenatal diagnosis. Prenatal diagnosis is recommended in order to avoid having another child with SMA in families with preexisting conditions.