Spinal and bulbar muscular atrophy
Last updated 18 Aug 2020
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Spinal and bulbar muscular atrophy, also known as Kennedy disease, is a disorder of specialized nerve cells that control muscle movement (motor neurons). These nerve cells originate in the spinal cord and the part of the brain that is connected to the spinal cord (the brainstem).
Description
Spinal and bulbar muscular atrophy, also known as Kennedy disease, is a disorder of specialized nerve cells that control muscle movement (motor neurons). These nerve cells originate in the spinal cord and the part of the brain that is connected to the spinal cord (the brainstem).
Spinal and bulbar muscular atrophy mainly affects males and is characterised by muscle weakness and wasting (atrophy) that usually begins in adulthood and worsens slowly over time. Muscle wasting in the arms and legs results in cramping; leg muscle weakness can also lead to difficulty walking and a tendency to fall. Certain muscles in the face and throat (bulbar muscles) are also affected, which causes progressive problems with swallowing and speech. Additionally, muscle twitches (fasciculations) are common. Some males with the disorder experience unusual breast development (gynecomastia) and may be unable to father a child (infertile).
Inheritance patterns
The source lists the following possible inheritance patterns: X-linked recessive. More than one pattern can apply in different cases.
Related genes
Other names
Bulbospinal muscular atrophy, X-linked
KD
Kennedy disease
Kennedy spinal and bulbar muscular atrophy
Kennedy's disease
SBMA
X-linked spinal and bulbar muscular atrophy
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Further reading and references
- Spinal and bulbar muscular atrophy; MedlinePlus, National Library of Medicine.
- Atsuta N, Watanabe H, Ito M, Banno H, Suzuki K, Katsuno M, Tanaka F, Tamakoshi A, Sobue G. Natural history of spinal and bulbar muscular atrophy (SBMA): a study of 223 Japanese patients. Brain. 2006 Jun;129(Pt 6):1446-55. doi: 10.1093/brain/awl096. Epub 2006 Apr 18.
- Finsterer J. Bulbar and spinal muscular atrophy (Kennedy's disease): a review. Eur J Neurol. 2009 May;16(5):556-61. doi: 10.1111/j.1468-1331.2009.02591.x.
- Finsterer J. Perspectives of Kennedy's disease. J Neurol Sci. 2010 Nov 15;298(1-2):1-10. doi: 10.1016/j.jns.2010.08.025. Epub 2010 Sep 16.
- Katsuno M, Banno H, Suzuki K, Adachi H, Tanaka F, Sobue G. Clinical features and molecular mechanisms of spinal and bulbar muscular atrophy (SBMA). Adv Exp Med Biol. 2010;685:64-74. doi: 10.1007/978-1-4419-6448-9_6.
- La Spada A. Spinal and Bulbar Muscular Atrophy. 1999 Feb 26 [updated 2026 Jan 8]. In: Adam MP, Bick S, Mirzaa GM, Wallace SE, Amemiya A, editors. GeneReviews(R) [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2026. Available from http://www.ncbi.nlm.nih.gov/books/NBK1333/
- Monks DA, Rao P, Mo K, Johansen JA, Lewis G, Kemp MQ. Androgen receptor and Kennedy disease/spinal bulbar muscular atrophy. Horm Behav. 2008 May;53(5):729-40. doi: 10.1016/j.yhbeh.2007.12.009. Epub 2008 Jan 5.
- Poletti A, Negri-Cesi P, Martini L. Reflections on the diseases linked to mutations of the androgen receptor. Endocrine. 2005 Dec;28(3):243-62. doi: 10.1385/ENDO:28:3:243.
- Schmidt BJ, Greenberg CR, Allingham-Hawkins DJ, Spriggs EL. Expression of X-linked bulbospinal muscular atrophy (Kennedy disease) in two homozygous women. Neurology. 2002 Sep 10;59(5):770-2. doi: 10.1212/wnl.59.5.770.
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