1. Cap myopathy caused by a mutation of the skeletal alpha-actin gene ACTA1
- Author
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Hung, Ryan M., Yoon, Grace, Hawkins, Cynthia E., Halliday, Willliam, Biggar, Doug, and Vajsar, Jiri
- Subjects
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MUSCLE diseases , *GENETIC mutation , *ACTIN , *PROTEIN genetics , *GENETIC disorders , *NEONATAL diseases , *SARCOLEMMA , *BIOPSY , *GENETICS - Abstract
Abstract: Cap myopathy is a congenital myopathy with cap-like structures under the sarcolemma. Mutations in TPM2 and TPM3 genes have been reported in cap myopathy so far. We report a newborn boy with persistent profound weakness who required gastro-jejunal tube feeding, tracheostomy and life-long ventilation until he died at 5years of age. Muscle biopsy at 5weeks of age was uninformative. Repeat biopsy at 4.5years revealed subsarcolemmally located caps that were immunopositive for alpha-actinin, actin and to some extent, desmin. EM confirmed loosely arranged thin filaments and paucity of thick filaments. Molecular analysis of ACTA1 gene identified a novel de novo Met47Val mutation. In addition to a new ACTA1 gene mutation, our case emphasizes the genetic heterogeneity of cap myopathy and its association with ACTA1 gene as well as the importance of repeat muscle biopsy in patients with undiagnosed muscle weakness. [Copyright &y& Elsevier]
- Published
- 2010
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