Spinal muscular atrophy

Synonyms: Spinal Muscular Atrophy (SMN1); Spinal Muscular Atrophy (SMN2)

Summary

Excerpted from the GeneReview: Spinal Muscular Atrophy

Spinal muscular atrophy (SMA) is characterized by muscle weakness and atrophy resulting from progressive degeneration and irreversible loss of the anterior horn cells in the spinal cord (i.e., lower motor neurons) and the brain stem nuclei. The onset of weakness ranges from before birth to adulthood. The weakness is symmetric, proximal greater than distal, and progressive. Before the genetic basis of SMA was understood, it was classified into clinical subtypes based on maximum motor function achieved; however, it is now apparent that the phenotype of SMN1-associated SMA spans a continuum without clear delineation of subtypes. With supportive care only, poor weight gain with growth failure, restrictive lung disease, scoliosis, and joint contractures are common complications; however, newly available targeted treatment options are changing the natural history of the disease.

Full text of GeneReview (by section):: Summary; GeneReview Scope; Diagnosis; Clinical Characteristics; Genetically Related (Allelic) Disorders; Differential Diagnosis; Management; Genetic Counseling; Resources; Molecular Genetics; Chapter Notes; References

Authors:: Thomas W Prior; Meganne E Leach; Erika L Finanger; view full author information

Available tests

120 tests are in the database for this condition.

Check Related conditions for additional relevant tests.

Clinical tests (120 available)

Biochemical Genetics Tests

Enzyme assay (14)

Molecular Genetics Tests

Genes See tests for all associated and related genes

Associated genes Help
Genes reported to contribute to the condition.
Related genes Help
Genes reported to contribute to conditions that are children of this condition in a hierarchy.

GEMIN2
Also known as: SIP1, SIP1-delta, GEMIN2
Summary: gem nuclear organelle associated protein 2
SMN1
216 tests
Also known as: BCD541, GEMIN1, SMA, SMA1, SMA2, SMA3, SMA4, SMA@, SMN, SMNT, T-BCD541, TDRD16A, SMN1
Summary: survival of motor neuron 1, telomeric
SMNDC1
4 tests
Also known as: SMNR, SPF30, TDRD16C, SMNDC1
Summary: survival motor neuron domain containing 1

Reviews

Clinical resources

Practice guidelines

ACMG ACT, 2020
American College of Medical Genetics and Genomics, Newborn Screening ACT Sheet, Exon 7 Deletion (Pathogenic Variant) in Survival Motor Neuron Gene (SMN1), Spinal Muscular Atrophy (SMA), 2020
ACMG ACT, 2018
ACMG Carrier Screening ACT Sheet Spinal Muscular Atrophy (SMA)

Molecular resources

Consumer resources

IMPORTANT NOTE: NIH does not independently verify information submitted to the GTR; it relies on submitters to provide information that is accurate and not misleading. NIH makes no endorsements of tests or laboratories listed in the GTR. GTR is not a substitute for medical advice. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.