U.S. flag

An official website of the United States government

Format

Send to:

Choose Destination

Myopathy, congenital, with structured cores and z-line abnormalities(MYOCOZ; MSCD; CMYP8)

MedGen UID:
1684705
Concept ID:
C5231445
Disease or Syndrome
Synonyms: CONGENITAL MYOPATHY 8; MULTIPLE STRUCTURED CORE DISEASE
 
Gene (location): ACTN2 (1q43)
 
Monarch Initiative: MONDO:0032852
OMIM®: 618654

Definition

Congenital myopathy-8 (CMYO8) is an autosomal dominant disorder of the skeletal muscle characterized by hypotonia and delayed motor development apparent from infancy or childhood, resulting in difficulties walking or loss of ambulation within the first few decades. Affected individuals show respiratory insufficiency, high-arched palate, and scoliosis; external ophthalmoplegia may also be present. Skeletal muscle biopsy shows cores and myofibrillar disorganization (Lornage et al., 2019). For a discussion of genetic heterogeneity of congenital myopathy, see CMYO1A (117000). [from OMIM]

Clinical features

From HPO
Cardiomegaly
MedGen UID:
5459
Concept ID:
C0018800
Finding
Increased size of the heart, clinically defined as an increased transverse diameter of the cardiac silhouette that is greater than or equal to 50% of the transverse diameter of the chest (increased cardiothoracic ratio) on a posterior-anterior projection of a chest radiograph or a computed tomography.
Congestive heart failure
MedGen UID:
9169
Concept ID:
C0018802
Disease or Syndrome
The presence of an abnormality of cardiac function that is responsible for the failure of the heart to pump blood at a rate that is commensurate with the needs of the tissues or a state in which abnormally elevated filling pressures are required for the heart to do so. Heart failure is frequently related to a defect in myocardial contraction.
Feeding difficulties in infancy
MedGen UID:
436211
Concept ID:
C2674608
Finding
Impaired feeding performance of an infant as manifested by difficulties such as weak and ineffective sucking, brief bursts of sucking, and falling asleep during sucking. There may be difficulties with chewing or maintaining attention.
Delayed ability to walk
MedGen UID:
66034
Concept ID:
C0241726
Finding
A failure to achieve the ability to walk at an appropriate developmental stage. Most children learn to walk in a series of stages, and learn to walk short distances independently between 12 and 15 months.
Scoliosis
MedGen UID:
11348
Concept ID:
C0036439
Disease or Syndrome
The presence of an abnormal lateral curvature of the spine.
Muscle weakness
MedGen UID:
57735
Concept ID:
C0151786
Finding
Reduced strength of muscles.
Proximal muscle weakness
MedGen UID:
113169
Concept ID:
C0221629
Finding
A lack of strength of the proximal muscles.
Muscle fiber atrophy
MedGen UID:
451037
Concept ID:
C0333751
Cell or Molecular Dysfunction
Weakness of facial musculature
MedGen UID:
98103
Concept ID:
C0427055
Disease or Syndrome
Reduced strength of one or more muscles innervated by the facial nerve (the seventh cranial nerve).
Distal muscle weakness
MedGen UID:
140883
Concept ID:
C0427065
Finding
Reduced strength of the musculature of the distal extremities.
Increased variability in muscle fiber diameter
MedGen UID:
336019
Concept ID:
C1843700
Finding
An abnormally high degree of muscle fiber size variation. This phenotypic feature can be observed upon muscle biopsy.
Type 1 muscle fiber predominance
MedGen UID:
344274
Concept ID:
C1854387
Finding
An abnormal predominance of type I muscle fibers (in general, this feature can only be observed on muscle biopsy).
Generalized hypotonia
MedGen UID:
346841
Concept ID:
C1858120
Finding
Generalized muscular hypotonia (abnormally low muscle tone).
Internally nucleated skeletal muscle fibers
MedGen UID:
1623054
Concept ID:
C4531255
Anatomical Abnormality
An abnormally increased proportion of nuclei of sarcomeres with an internal localization. Individual muscle fibers are syncytia, formed by embryonic fusion of many myoblasts or later, myosatellite cells. Each muscle fiber contains many nuclei, peripherally positioned immediately adjacent to the sarcolemmal membrane. In healthy muscle only 3-5% of fibers contain nuclei that are located internally, within the cell, but many disease processes lead to internal nuclei.
Abnormal Z disk morphology
MedGen UID:
1712600
Concept ID:
C5397583
Cell or Molecular Dysfunction
Any structural anomaly of the Z disk, which is the platelike region of a muscle sarcomere to which the plus ends of actin filaments are attached.
Respiratory insufficiency
MedGen UID:
11197
Concept ID:
C0035229
Pathologic Function
Impairment of gas exchange within the lungs secondary to a disease process, neoplasm, or trauma, possibly resulting in hypoxia, hypercarbia, or both, but not requiring intubation or mechanical ventilation. Patients are normally managed with pharmaceutical therapy, supplemental oxygen, or both.
Reduced vital capacity
MedGen UID:
141657
Concept ID:
C0476408
Finding
An abnormal reduction on the vital capacity, which is defined as the total lung capacity (volume of air in the lungs at maximal inflation) less the residual volume (i.e., volume of air in the lungs following maximal exhalation) of the lung.
High palate
MedGen UID:
66814
Concept ID:
C0240635
Congenital Abnormality
Height of the palate more than 2 SD above the mean (objective) or palatal height at the level of the first permanent molar more than twice the height of the teeth (subjective).
Ophthalmoparesis
MedGen UID:
155551
Concept ID:
C0751401
Sign or Symptom
Ophthalmoplegia is a paralysis or weakness of one or more of the muscles that control eye movement.
Weak extraocular muscles
MedGen UID:
347141
Concept ID:
C1859436
Finding

Recent clinical studies

Diagnosis

Lornage X, Romero NB, Grosgogeat CA, Malfatti E, Donkervoort S, Marchetti MM, Neuhaus SB, Foley AR, Labasse C, Schneider R, Carlier RY, Chao KR, Medne L, Deleuze JF, Orlikowski D, Bönnemann CG, Gupta VA, Fardeau M, Böhm J, Laporte J
Acta Neuropathol 2019 Mar;137(3):501-519. Epub 2019 Jan 30 doi: 10.1007/s00401-019-01963-8. PMID: 30701273Free PMC Article

Supplemental Content

Recent activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...