Genetic approaches to the nosology of muscular disease: myotonias and similar diseases.

Besides myotonic dystrophy some generalized myotonias exist, until now mostly diagnosed as "Thomsen's disease." It is questionable whether the dominant "myotonia congenita" is homogeneous. Surely there is at least one recessive type of generalized myotonia, which is also clinically different from Thomsen's disease. Paramyotonia congenita Eulenburg is a genetically independent type separated from paralysis periodica paramyotonia. Further diseases with myotonia and some other diseases of differential disgnostic importance with regard to myotonias are mentioned