myotubular myopathy

a genetically heterogenous, often fatal myopathy characterized by myofibers resembling those of early fetal muscle, i.e., with the nucleus located centrally and surrounded by a halo of apparently empty space. The X-linked form is most common and is caused by mutation in the MTM1 gene (locus: Xq28), which encodes a protein required for muscle cell differentiation. The autosomal dominant form is caused by mutation in any of several genes. The autosomal recessive form is caused by mutation in the BIN1 gene (locus: 2q14), which encodes a tumor suppressor protein. Called also centronuclear m.