Rare Endocrinology News

Disease Profile

X-linked myotubular myopathy

Prevalence
Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.

Unknown

Age of onset

Neonatal

ICD-10

G71.2

Inheritance

Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease

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Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype

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X-linked
dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.

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X-linked
recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder

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Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

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Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.

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Not applicable

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Other names (AKA)

X-linked centronuclear myopathy; XLCNM; XLMTM

Categories

Congenital and Genetic Diseases; Eye diseases; Nervous System Diseases

Summary

X-linked myotubular myopathy (XLMTM) is a type of centronuclear myopathy, which is a group of rare, inherited conditions that affect the muscles. XLMTM, specifically, occurs almost exclusively in males and is characterized by progressive muscle weakness (myopathy) and decreased muscle tone (hypotonia) that can range from mild to severe. The muscle problems impair the development of motor skills such as sitting, standing, and walking, and may disrupt primary functions such as breathing and feeding.[1][2] XLMTM is caused by changes (mutations) in the MTM1 gene and is inherited in an X-linked recessive manner.[1] Treatment is based on the signs and symptoms present in each person and may include physical and/or occupational therapy and assistive devices to help with mobility, eating and/or breathing.[2]

Symptoms

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
HPO ID
30%-79% of people have these symptoms
Areflexia
Absent tendon reflexes
0001284
Atrioventricular block
Interruption of electrical communication between upper and lower chambers of heart
0001678
Cavernous hemangioma
Collection of dilated blood vessels that forms mass
0001048
EMG abnormality
0003457
External ophthalmoplegia
Paralysis or weakness of muscles within or surrounding outer part of eye
0000544
Gait disturbance
Abnormal gait
Abnormal walk
Impaired gait

[ more ]

0001288
Head tremor
0002346
Mask-like facies
Expressionless face
Lack of facial expression
Mask-like facial appearance

[ more ]

0000298
Muscular hypotonia
Low or weak muscle tone
0001252
Ptosis
Drooping upper eyelid
0000508
Respiratory failure requiring assisted ventilation
0004887
Scoliosis
0002650
Seizure
0001250
Skeletal muscle atrophy
Muscle degeneration
Muscle wasting

[ more ]

0003202
Percent of people who have these symptoms is not available through HPO
Arachnodactyly
Long slender fingers
Spider fingers

[ more ]

0001166
Birth length greater than 97th percentile
0003517
Cryptorchidism
Undescended testes
Undescended testis

[ more ]

0000028
Decreased fetal movement
Less than 10 fetal movements in 12 hours
0001558
Decreased liver function
Liver dysfunction
0001410
Diaphragmatic eventration
0009110
Facial palsy
Bell's palsy
0010628
Flexion contracture
Flexed joint that cannot be straightened
0001371
Generalized muscle weakness
0003324
High palate
Elevated palate
Increased palatal height

[ more ]

0000218
Hydrocephalus
Too much cerebrospinal fluid in the brain
0000238
Hypokinesia
Decreased muscle movement
Decreased spontaneous movement
Decreased spontaneous movements

[ more ]

0002375
Long face
Elongation of face
Increased height of face
Increased length of face
Vertical elongation of face
Vertical enlargement of face
Vertical overgrowth of face

[ more ]

0000276
Macrocephaly
Increased size of skull
Large head
Large head circumference

[ more ]

0000256
Narrow face
Decreased breadth of face
Decreased width of face

[ more ]

0000275
Neck muscle weakness
Floppy neck
0000467
Neonatal respiratory distress
Infantile respiratory distress
Newborn respiratory distress
Respiratory distress, neonatal

[ more ]

0002643
Polyhydramnios
High levels of amniotic fluid
0001561
Pyloric stenosis
0002021
Respiratory failure
0002878
Severe muscular hypotonia
Severely decreased muscle tone
0006829
Slender toe
Narrow toe
0011308
X-linked recessive inheritance
0001419

Diagnosis

Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.

    Organizations

    Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

    Organizations Supporting this Disease

      Learn more

      These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

      Where to Start

        In-Depth Information

        • GeneReviews provides current, expert-authored, peer-reviewed, full-text articles describing the application of genetic testing to the diagnosis, management, and genetic counseling of patients with specific inherited conditions.
        • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
        • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
        • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
        • PubMed is a searchable database of medical literature and lists journal articles that discuss X-linked myotubular myopathy. Click on the link to view a sample search on this topic.

          References

          1. X-linked myotubular myopathy. Genetics Home Reference. July 2014; https://ghr.nlm.nih.gov/condition/x-linked-myotubular-myopathy.
          2. Das S, Dowling J, Pierson CR. X-Linked Centronuclear Myopathy. GeneReviews. October 6, 2011; https://www.ncbi.nlm.nih.gov/books/NBK1432/.