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GTR Home > Conditions/Phenotypes > Myopathy, congenital proximal, with minicore lesions


Congenital myopathy-9B (CMYP9B) is an autosomal recessive early-onset skeletal muscle disorder mainly affecting proximal muscles. Affected individuals have neonatal hypotonia followed by mildly delayed walking in childhood. Muscle weakness is slowly progressive, resulting in positive Gowers sign and difficulty running or climbing, but most patients remain ambulatory. Some patients develop respiratory involvement requiring ventilatory support, whereas cardiac function is unaffected. Muscle biopsy shows type 1 fiber predominance with disorganized Z-lines and multiminicore myopathy (Estan et al., 2019). For a discussion of genetic heterogeneity of congenital myopathy, see CMYP1A (117000). [from OMIM]

Available tests

2 tests are in the database for this condition.

Genes See tests for all associated and related genes

  • Also known as: CMYP9A, CMYP9B, FXR1P, MYOPMIL, MYORIBF, FXR1
    Summary: FMR1 autosomal homolog 1

Clinical features


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