- Emery–Dreifuss muscular dystrophy
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For other uses of "EDMD", see Everybody Draw Mohammed Day.
Emery–Dreifuss muscular dystrophy Classification and external resources ICD-10 G71.0 ICD-9 359.0-359.1 OMIM 181350 604929 310300 DiseasesDB 31705 33543 31704 MeSH D020389 Emery–Dreifuss muscular dystrophy is a condition that chiefly affects muscles used for movement (skeletal muscles) and heart (cardiac) muscle.
It is named after Alan Eglin H. Emery (1928–) and Fritz E. Dreifuss.[1][2][3]
Contents
Presentation
Among the earliest features of this disorder are joint deformities called contractures,[4] which restrict the movement of certain joints. Contractures become noticeable in early childhood to teenage years and most often involve the elbows, ankles, and neck. Most affected individuals also experience slowly progressive muscle weakness and wasting, beginning in muscles of the upper arms and lower legs and progressing to muscles in the shoulders and hips. A power chair or scooter or wheelchair may be needed by adulthood.
Almost all people with Emery–Dreifuss muscular dystrophy have heart problems by adulthood. In many cases, these heart problems stem from abnormalities of the electrical signals that control the heartbeat (cardiac conduction defects) and abnormal heart rhythms (arrhythmias). If untreated, these abnormalities can lead to an unusually slow heartbeat (bradycardia), fainting (syncope), and an increased risk of stroke and sudden death.
Classification
The types of Emery–Dreifuss muscular dystrophy are distinguished by their pattern of inheritance: X-linked, autosomal dominant, and autosomal recessive.
- Although the three types have similar signs and symptoms, researchers believe that the features of autosomal dominant Emery–Dreifuss muscular dystrophy are more variable than the other types. A small percentage of people with the autosomal dominant form experience heart problems without any weakness or wasting of skeletal muscles.
- X-linked Emery–Dreifuss muscular dystrophy is the most common form of this condition, affecting an estimated 1 in 100,000 people.
- The autosomal recessive type of this disorder appears to be very rare; only a few cases have been reported worldwide. The incidence of the autosomal dominant form is unknown.
Genetics
Mutations in the EMD and LMNA genes cause Emery–Dreifuss muscular dystrophy.[5] The EMD and LMNA genes provide instructions for making proteins that are components of the nuclear envelope, which surrounds the nucleus in cells. The nuclear envelope regulates the movement of molecules into and out of the nucleus, and researchers believe it may play a role in regulating the activity of certain genes.
Type OMIM Gene Description EDMD1 310300 EMD Most cases of Emery–Dreifuss muscular dystrophy are caused by mutations in the EMD gene. This gene provides instructions for making a protein called emerin, which appears to be essential for the normal function of skeletal and cardiac muscle. Most EMD mutations prevent the production of any functional emerin. It remains unclear how a lack of this protein results in the signs and symptoms of Emery-Dreifuss muscular dystrophy. EDMD2, EDMD3 181350 LMNA Less commonly, Emery–Dreifuss muscular dystrophy results from mutations in the LMNA gene. This gene provides instructions for making two very similar proteins, lamin A and lamin C. Most of the LMNA mutations that cause this condition result in the production of an altered version of these proteins. EDMD4 612998 SYNE1 EDMD5 612999 SYNE2 EDMD6 300696 FHL1 See also
- Laminopathies
- Noncompaction Cardiomyopathy
References
- ^ synd/1564 at Who Named It?
- ^ Emery AE, Dreifuss FE (1966). "Unusual type of benign x-linked muscular dystrophy". J. Neurol. Neurosurg. Psychiatr. 29 (4): 338–42. doi:10.1136/jnnp.29.4.338. PMC 1064196. PMID 5969090. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1064196.
- ^ Emery AE (1989). "Emery-Dreifuss syndrome". J. Med. Genet. 26 (10): 637–41. doi:10.1136/jmg.26.10.637. PMC 1015715. PMID 2685312. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1015715.
- ^ Muchir A, Pavlidis P, Bonne G, Hayashi YK, Worman HJ (August 2007). "Activation of MAPK in hearts of EMD null mice: similarities between mouse models of X-linked and autosomal dominant Emery Dreifuss muscular dystrophy". Hum. Mol. Genet. 16 (15): 1884–95. doi:10.1093/hmg/ddm137. PMID 17567779. http://hmg.oxfordjournals.org/cgi/pmidlookup?view=long&pmid=17567779.
- ^ Brown SC, Piercy RJ, Muntoni F, Sewry CA (December 2008). "Investigating the pathology of Emery-Dreifuss muscular dystrophy". Biochem. Soc. Trans. 36 (Pt 6): 1335–8. doi:10.1042/BST0361335. PMID 19021551. http://www.biochemsoctrans.org/bst/036/1335/bst0361335.htm.
External links
- Emery–Dreifuss muscular dystrophy at NLM Genetics Home Reference
- GeneReviews/NCBI/NIH/UW entry on Emery–Dreifuss muscular dystrophy
- GeneReviews/NCBI/NIH/UW entry on SYNE1-Related Autosomal Recessive Cerebellar Ataxia
Muscular dystrophy The Nine Primary Muscular Dystrophies Related topicsNational/International Organizations US government Institutes and Legislation National/International Events MDA Labor Day Telethon (USA) • Décrypthon (France)Recent or Ongoing Clinical Trials Diseases of myoneural junction and muscle / neuromuscular disease (G70–G73, 358–359) Neuromuscular-
junction diseaseautoimmune (Myasthenia gravis, Lambert–Eaton myasthenic syndrome)Myopathy/
congenital myopathyMuscular dystrophy
(DAPC)ADAROther structuralOtherOtherCytoskeletal defects Microfilaments OtherFibrillin (Marfan syndrome, Weill-Marchesani syndrome, ) · Filamin (FG syndrome 2, Boomerang dysplasia, Larsen syndrome, Terminal osseous dysplasia with pigmentary defects)IF 1/2Keratinopathy (keratosis, keratoderma, hyperkeratosis): KRT1 (Striate palmoplantar keratoderma 3, Epidermolytic hyperkeratosis, IHCM) · KRT2E (Ichthyosis bullosa of Siemens) · KRT3 (Meesmann juvenile epithelial corneal dystrophy) · KRT4 (White sponge nevus) · KRT5 (Epidermolysis bullosa simplex) · KRT8 (Familial cirrhosis) · KRT10 (Epidermolytic hyperkeratosis) · KRT12 (Meesmann juvenile epithelial corneal dystrophy) · KRT13 (White sponge nevus) · KRT14 (Epidermolysis bullosa simplex) · KRT17 (Steatocystoma multiplex) · KRT18 (Familial cirrhosis) · KRT81/KRT83/KRT86 (Monilethrix) · Naegeli–Franceschetti–Jadassohn syndrome · Reticular pigmented anomaly of the flexures345Laminopathy: LMNA (Mandibuloacral dysplasia, Dunnigan Familial partial lipodystrophy, Emery-Dreifuss muscular dystrophy 2, Limb-girdle muscular dystrophy 1B, Charcot–Marie–Tooth disease 2B1) · LMNB (Barraquer–Simons syndrome) · LEMD3 (Buschke–Ollendorff syndrome, Osteopoikilosis) · LBR (Pelger-Huet anomaly, Hydrops-ectopic calcification-moth-eaten skeletal dysplasia)Microtubules OtherTauopathy · Cavernous venous malformationMembrane Catenin Other desmoplakin: Striate palmoplantar keratoderma 2 · Carvajal syndrome · Arrhythmogenic right ventricular dysplasia 8
plectin: Epidermolysis bullosa simplex with muscular dystrophy · Epidermolysis bullosa simplex of Ogna
plakophilin: Skin fragility syndrome · Arrhythmogenic right ventricular dysplasia 9
centrosome: PCNT (Microcephalic osteodysplastic primordial dwarfism type II)Categories:
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