Making sense of the limb-girdle muscular dystrophies.
The clinical heterogeneity which has long been recognized in the limb-girdle muscular dystrophies (LGMD) has been shown to relate to the involvement of a large number of different genes. At least eight forms of autosomal recessive LGMD and three forms of autosomal dominant disease are now recognized and can be defined by the primary gene or protein involved, or by a genetic localization. These advances have combined the approaches of positional cloning and candidate gene analysis to great effect, with the pivotal role of the dystrophin-associated complex confirmed through the involvement of at least four dystrophin-associated proteins in different subtypes of autosomal recessive LGMD (the sarcoglycanopathies). Two novel mechanisms may have to be postulated to explain the involvement of the calpain 3 and dysferlin genes in other forms of LGMD. Using the diagnostic tools which have become available as a result of this increased understanding, the clinical features of the various subtypes are also becoming clearer, with useful diagnostic and prognostic information at last available to the practising clinician.
Bushby
K M
KM
Department of Biochemistry and Genetics, University of Newcastle-upon-Tyne, UK. kate.bushby@ncl.ac.uk
D002154:Calpain / Q000235:genetics; D002874:Chromosome Mapping; D003598:Cytoskeletal Proteins / Q000235:genetics; D000073939:Dysferlin; D049030:Dystroglycans; D005808:Genes, Recessive; D006801:Humans; D007527:Isoenzymes; D008562:Membrane Glycoproteins / Q000235:genetics; D008565:Membrane Proteins; D009124:Muscle Proteins / Q000235:genetics; D009136:Muscular Dystrophies / Q000145:classification / Q000235:genetics*; D010446:Peptide Fragments / Q000235:genetics; D049031:Sarcoglycans
D003598:Cytoskeletal Proteins; C483081:DAG1 protein, human; C114839:DYSF protein, human; D000073939:Dysferlin; D007527:Isoenzymes; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D009124:Muscle Proteins; D010446:Peptide Fragments; D049031:Sarcoglycans; D049030:Dystroglycans; C105884:CAPN3 protein, human; D002154:Calpain