The limb-girdle muscular dystrophies: diagnostic guidelines.

At least 11 different disorders can be recognized to be genetically distinct within the group of muscle diseases known as the limb-girdle muscular dystrophies. Direct gene or protein based tests are available to confirm the diagnosis in one autosomal dominant and six autosomal recessive forms. In these disorders, therefore, a definition based on molecular pathology is becoming possible. Clinical studies in the genetically defined subgroups may also help to determine phenotypic correlates for the various diseases. An integrated approach to diagnosis in this group, based on clinical observations supported by the result of genetic and protein studies, is likely to provide the optimum level of information.