Centronuclear Myopathy

National Organization for Rare Disorders, Inc.

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It is possible that the main title of the report Centronuclear Myopathy is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.


  • CNM
  • autosomal dominant centronuclear myopathy (AD-CNM)
  • autosomal recessive centronuclear myopathy (AR-CNM)

Disorder Subdivisions

  • None

General Discussion

Centronuclear myopathy (CNM) is an umbrella term for a group of rare genetic muscle disorders. These disorders are characterized by muscle weakness that can range from mild to profound. Symptoms are often present at birth in the severe forms, but may first develop at any point during life, although onset in adulthood is unusual. There are several genetic forms of CNM including an X-linked form known as myotubular myopathy (XLMTM) and a few autosomal forms, usually referred to as centronuclear myopathy. Autosomal refers to genes that are found on autosomes, or chromosomes other than the X or Y chromosomes (sex chromosomes). Generally, the autosomal forms are less severe than XLMTM, however, in rare cases, individuals with an autosomal form can develop severe complications that are similar to those seen in XLMTM. CNMs derive their name from the abnormal location of the nucleus in the center of the muscle fiber (muscle cell) rather than the normal position on the edge. Centronuclear myopathies can be further classified into the larger, broader category of congenital myopathy, a group of genetic muscle disorders that are present at birth.

Common symptoms include mild to profound muscle weakness and diminished muscle tone (hypotonia or "floppiness"). In more severe cases, feeding difficulties and potentially severe breathing complications (respiratory distress) may occur. Feeding difficulties and respiratory distress develop because of weakness of the muscles that are involved in swallowing and breathing. Involvement of the muscles controlling eye movements is common in all different forms. The overall severity of the disorder can range from mildly affected individuals to individuals who develop severe, life-threatening complications during infancy and early childhood. Three different genes, DNM2, BIN1, and RYR1, have been identified that cause autosomal forms of CNM. XLMTM is caused by mutations to the myotubularin (MTM1) gene.

In the medical literature, centronuclear myopathy (CNM) is generally used for the autosomal forms of the disorder and myotubular myopathy is generally used for the X-linked form (XLMTM). Distinguishing between the X-linked myotubular form and the autosomal forms of CNM is essential as the symptoms are usually more severe in the X-linked form. NORD has a separate report on X-linked myotubular myopathy that describes that form in greater detail. This report specifically deals with the autosomal forms of centronuclear myopathy.


CLIMB (Children Living with Inherited Metabolic Diseases)
Climb Building
176 Nantwich Road
Crewe, CW2 6BG
United Kingdom
Tel: 4408452412173
Fax: 4408452412174
Email: enquiries@climb.org.uk
Internet: http://www.CLIMB.org.uk

Myotubular Myopathy Resource Group
2602 Quaker Drive
Texas City, TX 77590
Tel: (409)945-8569
Email: info@mtmrg.org
Internet: http://www.mtmrg.org

Contact A Family
209-211 City Road
London, EC1V 1JN
United Kingdom
Tel: 02076088700
Fax: 02076088701
Tel: 08088083555
Email: info@cafamily.org.uk
Internet: http://www.cafamily.org.uk/

Muscular Dystrophy Association
3300 East Sunrise Drive
Tucson, AZ 85718-3208
Tel: (520)529-2000
Fax: (520)529-5300
Tel: (800)572-1717
Email: mda@mdausa.org
Internet: http://www.mda.org/

Muscular Dystrophy Campaign
61 Southwark Street
London, SE1 0HL
United Kingdom
Tel: 02078034800
Email: info@muscular-dystrophy.org
Internet: http://www.muscular-dystrophy.org

NIH/National Institute of Neurological Disorders and Stroke
P.O. Box 5801
Bethesda, MD 20824
Tel: (301)496-5751
Fax: (301)402-2186
Tel: (800)352-9424
TDD: (301)468-5981
Internet: http://www.ninds.nih.gov/

European Alliance of Neuromuscular Disorders Associations
MDG Malta 4
Gzira Road
Gzira, GAR 04
Tel: 0035621346688
Fax: 0035621318024
Email: eamda@hotmail.com
Internet: http://www.eamda.net

Genetic and Rare Diseases (GARD) Information Center
PO Box 8126
Gaithersburg, MD 20898-8126
Tel: (301)251-4925
Fax: (301)251-4911
Tel: (888)205-2311
TDD: (888)205-3223
Internet: http://rarediseases.info.nih.gov/GARD/

Cure CMD (Congenital Muscular Dystrophy)
P.O. Box 701
Olathe, KS 66051
Tel: (866)400-3626
Email: info@curecmd.com
Internet: http://www.curecmd.org

Joshua Frase Foundation for Congential Myopathy Research
P.O. Box 2041
Ponte Vedra Beach, FL 32004
Tel: (904)273-9818
Fax: (904)607-1358
Email: info@joshuafrase.org
Internet: www.joshuafrase.org

Myotubular Trust
15a Barnard Road
London SW11 1QT
Tel: 07518 113692
Email: contact@myotubulartrust.org
Internet: http://www.myotubulartrust.org

For a Complete Report

This is an abstract of a report from the National Organization for Rare Disorders (NORD). A copy of the complete report can be downloaded free from the NORD website for registered users. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational therapies (if available), and references from medical literature. For a full-text version of this topic, go to www.rarediseases.org and click on Rare Disease Database under "Rare Disease Information".

The information provided in this report is not intended for diagnostic purposes. It is provided for informational purposes only. NORD recommends that affected individuals seek the advice or counsel of their own personal physicians.

It is possible that the title of this topic is not the name you selected. Please check the Synonyms listing to find the alternate name(s) and Disorder Subdivision(s) covered by this report

This disease entry is based upon medical information available through the date at the end of the topic. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder.

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Last Updated:  5/20/2013
Copyright  2013 National Organization for Rare Disorders, Inc.