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Congenital myopathy with fiber type disproportion

Synonyms
Congenital Fiber-Type Disproportion; Congenital fiber-type disproportion myopathy
Modes of inheritance
Autosomal recessive inheritance (Orphanet)
Autosomal dominant inheritance (Orphanet)
X-linked recessive inheritance (Orphanet)

Summary

Congenital fiber-type disproportion is a condition that primarily affects skeletal muscles, which are muscles used for movement. People with this condition typically experience muscle weakness (myopathy), particularly in the muscles of the shoulders, upper arms, hips, and thighs. Weakness can also affect the muscles of the face and muscles that control eye movement (ophthalmoplegia), sometimes causing droopy eyelids (ptosis). Individuals with congenital fiber-type disproportion generally have a long face, a high arch in the roof of the mouth (high-arched palate), and crowded teeth.\n\nIndividuals with congenital fiber-type disproportion may have joint deformities (contractures) and an abnormally curved lower back (lordosis) or a spine that curves to the side (scoliosis). Approximately 30 percent of people with this disorder experience mild to severe breathing problems related to weakness of muscles needed for breathing. Some people who experience these breathing problems require use of a machine to help regulate their breathing at night (noninvasive mechanical ventilation), and occasionally during the day as well. About 30 percent of affected individuals have difficulty swallowing due to muscle weakness in the throat. Rarely, people with this condition have a weakened and enlarged heart muscle (dilated cardiomyopathy).\n\nThe severity of congenital fiber-type disproportion varies widely. It is estimated that up to 25 percent of affected individuals experience severe muscle weakness at birth and die in infancy or childhood. Others have only mild muscle weakness that becomes apparent in adulthood. Most often, the signs and symptoms of this condition appear by age 1. The first signs of this condition are usually decreased muscle tone (hypotonia) and muscle weakness. In most cases, muscle weakness does not worsen over time, and in some instances it may improve. Although motor skills such as standing and walking may be delayed, many affected children eventually learn to walk. These individuals often have less stamina than their peers, but they remain active. Rarely, people with this condition have a progressive decline in muscle strength over time. These individuals may lose the ability to walk and require wheelchair assistance. [from MedlinePlus Genetics]

Available tests

109 tests are in the database for this condition.

Check Related conditions for additional relevant tests.

Clinical tests (108 available)

Molecular Genetics Tests

Research tests

Genes See tests for all associated and related genes

  • Also known as: ACTA, ASMA, CFTD, CFTD1, CFTDM, CMYP2A, CMYP2B, CMYP2C, MPFD, NEM1, NEM2, NEM3, SHPM, ACTA1
    Summary: actin alpha 1, skeletal muscle

  • Also known as: CMD1S, CMH1, CMYP7A, CMYP7B, MPD1, MYHCB, SPMD, SPMM, MYH7
    Summary: myosin heavy chain 7

  • Also known as: CCO, CMYP1A, CMYP1B, KDS, MHS, MHS1, PPP1R137, RYDR, RYR, RYR-1, SKRR, RYR1
    Summary: ryanodine receptor 1

  • Also known as: CFTD, CMYP3, MDRS1, RSMD1, RSS, SELN, SEPN1, SELENON
    Summary: selenoprotein N

  • Also known as: AMCD1, CMYP23, DA1, DA2B, DA2B4, HEL-S-273, NEM4, TMSB, TPM2
    Summary: tropomyosin 2

  • Also known as: CAPM1, CFTD, CMYP4A, CMYP4B, HEL-189, HEL-S-82p, NEM1, OK/SW-cl.5, TM-5, TM3, TM30, TM30nm, TM5, TPM3nu, TPMsk3, TRK, hscp30, TPM3
    Summary: tropomyosin 3

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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