Format

Send to:

Choose Destination

Links from PubMed

Severe X-linked myotubular myopathy(CNMX)

MedGen UID:
98374
Concept ID:
C0410203
Congenital Abnormality
Synonyms: CNMX; MYOTUBULAR MYOPATHY 1; Myotubular myopathy, X-linked; X-linked centronuclear myopathy
Modes of inheritance:
X-linked recessive inheritance
MedGen UID:
375779
Concept ID:
C1845977
Finding
Sources: HPO, OMIM, Orphanet
A mode of inheritance that is observed for recessive traits related to a gene encoded on the X chromosome. In the context of medical genetics, X-linked recessive disorders manifest in males (who have one copy of the X chromosome and are thus hemizygotes), but generally not in female heterozygotes who have one mutant and one normal allele.
X-linked recessive inheritance (HPO, OMIM, Orphanet)
SNOMED CT: X-linked centronuclear myopathy (46804001); Severe x-linked myotubular myopathy (46804001)
 
Gene (location): MTM1 (Xq28)
OMIM®: 310400
Orphanet: ORPHA596

Disease characteristics

Excerpted from the GeneReview: X-Linked Centronuclear Myopathy
X-linked centronuclear myopathy (XLCNM) (also known as myotubular myopathy [MTM]) is characterized by muscle weakness that ranges from severe to mild. Severe (classic) XLCNM presents prenatally with polyhydramnios and decreased fetal movement and in newborns with weakness, hypotonia, and respiratory distress. Affected males have significantly delayed motor milestones and most fail to achieve independent ambulation. Weakness is profound and often involves facial and extraocular muscles. Respiratory failure is nearly uniform, with most affected individuals requiring 24-hour ventilatory assistance. A minority of males with severe XLCNM die in infancy. Males with moderate XLCNM achieve motor milestones more quickly than males with the severe form; about 40% require no ventilator support or intermittent support. Males with mild XLCNM may require ventilatory support only in the newborn period; they have minimally delayed motor milestones, are able to walk, and may lack myopathic facies. The muscle disease of XLCNM is not obviously progressive. Female carriers of XLCNM are generally asymptomatic, although rare manifesting heterozygotes have been described. [from GeneReviews]
Authors:
Soma Das  |  James Dowling  |  Christopher R Pierson   view full author information

Additional description

From GHR
X-linked myotubular myopathy is a condition that primarily affects muscles used for movement (skeletal muscles) and occurs almost exclusively in males. People with this condition have muscle weakness (myopathy) and decreased muscle tone (hypotonia) that are usually evident at birth.The muscle problems in X-linked myotubular myopathy impair the development of motor skills such as sitting, standing, and walking. Affected infants may also have difficulties with feeding due to muscle weakness. Individuals with this condition often do not have the muscle strength to breathe on their own and must be supported with a machine to help them breathe (mechanical ventilation). Some affected individuals need breathing assistance only periodically, typically during sleep, while others require it continuously. People with X-linked myotubular myopathy may also have weakness in the muscles that control eye movement (ophthalmoplegia), weakness in other muscles of the face, and absent reflexes (areflexia).In X-linked myotubular myopathy, muscle weakness often disrupts normal bone development and can lead to fragile bones, an abnormal curvature of the spine (scoliosis), and joint deformities (contractures) of the hips and knees. People with X-linked myotubular myopathy may have a large head with a narrow and elongated face and a high, arched roof of the mouth (palate). They may also have liver disease, recurrent ear and respiratory infections, or seizures.Because of their severe breathing problems, individuals with X-linked myotubular myopathy usually survive only into early childhood; however, some people with this condition have lived into adulthood.X-linked myotubular myopathy is a member of a group of disorders called centronuclear myopathies. In centronuclear myopathies, the nucleus is found at the center of many rod-shaped muscle cells instead of at either end, where it is normally located.  https://ghr.nlm.nih.gov/condition/x-linked-myotubular-myopathy

Clinical features

Arachnodactyly
MedGen UID:
2047
Concept ID:
C0003706
Congenital Abnormality
Cryptorchidism, unilateral or bilateral
MedGen UID:
8192
Concept ID:
C0010417
Congenital Abnormality
Cryptorchidism, or failure of testicular descent, is a common human congenital abnormality with a multifactorial etiology that likely reflects the involvement of endocrine, environmental, and hereditary factors. Cryptorchidism can result in infertility and increases risk for testicular tumors. Testicular descent from abdomen to scrotum occurs in 2 distinct phases: the transabdominal phase and the inguinoscrotal phase (summary by Gorlov et al., 2002).
Diaphragmatic eventration
MedGen UID:
8359
Concept ID:
C0011981
Congenital Abnormality
Polyhydramnios
MedGen UID:
6936
Concept ID:
C0020224
Pathologic Function
Hydrocephalus
MedGen UID:
9335
Concept ID:
C0020255
Disease or Syndrome
Autosomal recessive nonsyndromic hydrocephalus is characterized by onset in utero of enlarged ventricles due to a disturbance of cerebrospinal fluid accumulation. Affected individuals may have neurologic impairment (summary by Drielsma et al., 2012). Hydrocephalus can also be caused by Arnold-Chiari malformation, atresia of foramen of Magendie, stenosis of aqueduct of Sylvius (307000), toxoplasmosis, hydranencephaly, etc. Furthermore, it develops in infancy or childhood in achondroplasia (100800) and in Hurler disease (607014). Genetic Heterogeneity of Congenital Hydrocephalus See also autosomal recessive HYC2 (615219), caused by mutation in the MPDZ gene (603785) on chromosome 9p. An X-linked form (307000) is caused by mutation in the L1CAM gene on (308840) on chromosome Xq28.
Pyloric stenosis
MedGen UID:
18780
Concept ID:
C0034194
Pathologic Function
Hypokinesia
MedGen UID:
39223
Concept ID:
C0086439
Finding
External ophthalmoplegia
MedGen UID:
57662
Concept ID:
C0162292
Disease or Syndrome
Decreased liver function
MedGen UID:
65430
Concept ID:
C0232744
Finding
Reduced ability of the liver to perform its functions.
Areflexia
MedGen UID:
115943
Concept ID:
C0234146
Finding
Decreased fetal movement
MedGen UID:
68618
Concept ID:
C0235659
Finding
Neck muscle weakness
MedGen UID:
66808
Concept ID:
C0240479
Finding
High palate
MedGen UID:
66814
Concept ID:
C0240635
Congenital Abnormality
Flexion contracture
MedGen UID:
83069
Concept ID:
C0333068
Anatomical Abnormality
A flexion contracture is a bent (flexed) joint that cannot be straightened actively or passively. It is thus a chronic loss of joint motion due to structural changes in muscle, tendons, ligaments, or skin that prevents normal movement of joints.
Facial palsy
MedGen UID:
87660
Concept ID:
C0376175
Disease or Syndrome
Facial nerve palsy is a dysfunction of cranial nerve VII (the facial nerve) that results in inability to control facial muscles on the affected side with weakness of the muscles of facial expression and eye closure. This can either be present in unilateral or bilateral form.
Generalized muscle weakness
MedGen UID:
155433
Concept ID:
C0746674
Sign or Symptom
Long face
MedGen UID:
324419
Concept ID:
C1836047
Finding
Narrow face
MedGen UID:
373334
Concept ID:
C1837463
Finding
Bizygomatic (upper face) and bigonial (lower face) width are both more than 2 standard deviations below the mean (objective); or, an apparent reduction in the width of the upper and lower face (subjective).
Birth length greater than 97th percentile
MedGen UID:
326443
Concept ID:
C1839271
Finding
Severe muscular hypotonia
MedGen UID:
326544
Concept ID:
C1839630
Finding
Slender toe
MedGen UID:
866814
Concept ID:
C4021168
Finding
Respiratory failure requiring assisted ventilation
MedGen UID:
870821
Concept ID:
C4025279
Finding
Increased head circumference
MedGen UID:
909477
Concept ID:
C4083076
Finding
Occipitofrontal (head) circumference greater than 97th centile compared to appropriate, age matched, sex-matched normal standards. Alternatively, a apparently increased size of the cranium.
Neonatal respiratory distress
MedGen UID:
924182
Concept ID:
C4281993
Finding
Respiratory difficulty as newborn.

Term Hierarchy

CClinical test,  RResearch test,  OOMIM,  GGeneReviews,  VClinVar  
Follow this link to review classifications for Severe X-linked myotubular myopathy in Orphanet.

Professional guidelines

PubMed

Biancalana V, Beggs AH, Das S, Jungbluth H, Kress W, Nishino I, North K, Romero NB, Laporte J
Eur J Hum Genet 2012 Oct;20(10) Epub 2012 May 23 doi: 10.1038/ejhg.2012.91. PMID: 22617344Free PMC Article

Recent clinical studies

Prognosis

Tyson RW, Ringel SP, Manchester DK, Shikes RH, Goodman SI
Pediatr Pathol 1992 Jul-Aug;12(4):535-43. PMID: 1409152

Supplemental Content

Recent activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...
Support Center