This article reviews recent advances in the understanding of nemaline myopathy, with a focus on the genetic basis of the disorder, histology, and pathogenesis.
Pathogenic mutations have been identified in eight genes and there is evidence of further genetic heterogeneity in nemaline myopathy. Clinical presentation, histological features on skeletal muscle biopsy, and pattern of changes on muscle MRI may guide prioritization of molecular genetic testing. It is anticipated that use of new technologies such as whole exome sequencing and comparative genomic hybridization will increase the number of genes associated with nemaline myopathy and the proportion of patients in whom the genetic basis of the disorder is identified. Single fiber studies and animal models continue to add to understanding of the pathogenesis of this disorder. Current management focuses on supportive treatment; however, encouraging advances are emerging for the future.
Recent advances in understanding of nemaline myopathy have important implications for clinical practice and for genetic diagnosis of patients with nemaline myopathy.
aInstitut de Myologie, Groupe Hospitalier-Universitaire La Pitié-Salpêtrière, AP-HP, UPMC-Paris6 UR76, INSERM UMR974, CNRS UMR 7215, Paris, France
bInstitute for Neuroscience and Muscle Research, Children's Hospital at Westmead, University of Sydney, Sydney, New South Wales, Australia
Correspondence to Norma B. Romero, Unité de Morphologie Neuromusculaire, Institut de Myologie, Pavillon Risler, Groupe Hospitalier Universitaire Pitié-Salpêtrière, 47 boulevard de l’Hôpital, F-75 651 Paris Cedex 13, France. Tel: +33 1 42 16 23 23; e-mail: email@example.com