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Centronuclear Myopathy

National Organization for Rare Disorders, Inc.


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

  • BIN1-related CNM
  • DNM2-related CNM
  • RYR1-related CNM
  • X-linked myotubular myopathy (XLMTM)

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



Myotubular Myopathy Resource Group

2602 Quaker Drive

Texas City, TX 77590

Tel: (409)945-8569



Contact A Family

209-211 City Road

London, EC1V 1JN

United Kingdom

Tel: 02076088700

Fax: 02076088701

Tel: 08088083555



Muscular Dystrophy Association

3300 East Sunrise Drive

Tucson, AZ 85718-3208


Tel: (520)529-2000

Fax: (520)529-5300

Tel: (800)572-1717



Muscular Dystrophy Campaign

61 Southwark Street

London, SE1 0HL

United Kingdom

Tel: 02078034800



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


European Alliance of Neuromuscular Disorders Associations

MDG Malta 4

Gzira Road

Gzira, GAR 04


Tel: 0035621346688

Fax: 0035621318024



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


Cure CMD (Congenital Muscular Dystrophy)

P.O. Box 701

Olathe, KS 66051


Tel: (866)400-3626



Joshua Frase Foundation

222 Forbes Rd.

Suite 207

Braintree, MA 02184

Tel: (904)273-9818

Fax: (904)607-1358



Myotubular Trust

15a Barnard Road

London SW11 1QT

Tel: 07518 113692



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 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.

For additional information and assistance about rare disorders, please contact the National Organization for Rare Disorders at P.O. Box 1968, Danbury, CT 06813-1968; phone (203) 744-0100; web site or email

Last Updated:  5/20/2013

Copyright  2013 National Organization for Rare Disorders, Inc.

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