Background: Over the past 3 years, the genetics of the myotonic diseases have been
substantially elaborated. Three genetically different groups of myotonic disease can be
discerned:(1) the chloride channel myotonias,(2) the adynamiaparamyotonia complex, and
(3) myotonic dystrophy. Methods and Results: Electrophysiology has suggested and
molecular biology has proven that the diseases belonging to the adynamia-paramyotonia
complex, ie, paramyotonia congenita, hyperkalemic and normokalemic periodic paralysis …