Centronuclear myopathy

Centronuclear myopathy
Other names	CNM
Muscle biopsy from the quadriceps taken at 3 months of age from a girl with X-linked centronuclear ("myotubular") myopathy due to a mutation in the myotubularin (MTM1) gene and extremely skewed X-inactivation (H&E stain, transverse section). Note marked variability in fibre size, moderate increase in connective tissue and numerous central nuclei.
Specialty	Neurology

Centronuclear myopathies (CNM) are a group of congenital myopathies where cell nuclei are abnormally located in the center of muscle cells instead of their normal location at the periphery.

Symptoms of CNM include severe hypotonia, hypoxia-requiring breathing assistance, and scaphocephaly. Among centronuclear myopathies, the X-linked myotubular myopathy form typically presents at birth, and is thus considered a congenital myopathy. However, some centronuclear myopathies may present later in life.