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GTR Home > Conditions/Phenotypes > Myofibrillar myopathy 8

Myofibrillar myopathy 8

Summary

Myofibrillar myopathy-8 (MFM8) is an autosomal recessive myopathy characterized by slowly progressive proximal muscle weakness and atrophy affecting the upper and lower limbs, resulting in increased falls, gait problems, difficulty running or climbing stairs, and upper limb weakness or scapular winging. Some patients develop distal muscle weakness and atrophy. The phenotype may also be consistent with a clinical diagnosis of limb-girdle muscular dystrophy (LGMD). Age at symptom onset ranges from infancy to adulthood. Ambulation is generally preserved and cardiac involvement is rare, but respiratory compromise with decreased forced vital capacity often occurs. Muscle biopsy shows a mix of myopathic features, including myofibrillar inclusions and sarcomeric disorganization; some patients have been reported to have dystrophic changes on muscle biopsy (O'Grady et al., 2016; Daimaguler et al., 2021). There is significant phenotypic variation, even in patients with the same mutation, which must be taken into account when counseling affecting individuals (Woods et al., 2020). For a general phenotypic description and a discussion of genetic heterogeneity of myofibrillar myopathy, see MFM1 (601419). [from OMIM]

Available tests

18 tests are in the database for this condition.

Clinical tests (18 available)

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: MFM8, PYROXD1
    Summary: pyridine nucleotide-disulphide oxidoreductase domain 1

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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