This report describes general characteristics of the group of diseases classified as spinal muscular atrophy (SMA). Spinal muscular atrophy a genetically heterogeneous disorder, with multiple genes and mapped loci. A listing of SMA subtypes may be found in the table below, with links to more detailed reports for subtypes that have been investigated using fly models.
[updated July 2016 by FlyBase; FBrf0222196]
Spinal muscular atrophy (SMA) is characterized by progressive muscle weakness resulting from degeneration and loss of the anterior horn cells (i.e., lower motor neurons) in the spinal cord and the brain stem nuclei. Onset ranges from before birth to adolescence or young adulthood. Poor weight gain, sleep difficulties, pneumonia, scoliosis, and joint contractures are common complications. [From GeneReviews, Spinal Muscular Atrophy, pubmed:20301526 2016.07.11]