The classifications of the dysferlinopathies mainly include limb-girdle muscular dystrophy 2B (LGMD2B) with predominantly proximal weakness, Miyoshi myopathy (MM) with calf muscle weakness and atrophy, and distal myopathy with anterior tibial onset (DMAT) with tibialis muscle atrophy.
Mutations in dysferlin lead to Limb Girdle Muscular Dystrophy 2B (LGMD2B), Miyoshi Myopathy (MM), and Distal Myopathy with Anterior Tibialis onset (DMAT).
This approach may also be applicable to limb-girdle muscular dystrophy type 2B (LGMD2B), Myoshi myopathy (MM) and distal myopathy with anterior tibial onset (DMAT), which are caused by mutations in the dysferlin-encoding DYSF gene.
There were 28 patients (20 men and eight women) presenting with manifestations of distal myopathy or LGMD2B and had absence of dysferlin staining on IHC.
Mutations in dysferlin gene cause several types of muscular dystrophy in humans, including the limb-girdle muscular dystrophy type 2B and the distal muscular dystrophy of Miyoshi.
We speculate that dysferlin is involved in the pathogenesis of the myopathy in these patients, which may represent a new disease entity presenting as a distal myopathy.
The dysferlin gene, a strong candidate gene responsible for two other distal myopathies in the same region, is located centromeric to PAC3-H52 and can thereby formally be excluded as cause for WDM.
The dysferlin gene, a strong candidate gene responsible for two other distal myopathies in the same region, is located centromeric to PAC3-H52 and can thereby formally be excluded as cause for WDM.
Dysferlin immunohistochemical and Western blot analyses allowed us to identify six patients with dysferlin deficiency: one with distal myopathy, four with limb girdle myopathy and one with hyperCKemia.
Dysferlin, the protein product of the gene mutated in patients with an autosomal recessive limb-girdle muscular dystrophy type 2B (LGMD2B) and a distal muscular dystrophy, Miyoshi myopathy, is homologous to a Caenorhabditis elegans spermatogenesis factor, FER-1.
Due to the rarity of these myopathies, if some clinical patterns (such as distal myopathy associated with cardiomyopathy due to desmin mutations) are now well known, surprises remain possible and should lead to systematic testing of the known genes in case of a typical histological presentation.
The desmuslin protein interacts with and is closely related to desmin, a protein encoded by a locus mutated in some forms of hereditary distal myopathy.
A missense mutation in the desmin rod domain is associated with autosomal dominant distal myopathy, and exerts a dominant negative effect on filament formation.
This family shows a hereditary distal myopathy with some features in common with previously-reported cases in which biopsies showed cytoplasmic inclusion bodies containing desmin.
Recessive mutations in anoctamin-5 (ANO5) are causative for limb-girdle muscular dystrophy (LGMD) 2 L and non-dysferlin Miyoshi-like distal myopathy (MMD3).