ABSTRACT
One of the intriguing developments in the biology of excitable membranes has been the discovery that several heritable disorders are due to mutations of ion channel genes. The integrated function of many ion channels is required for the generation and propagation of action potentials over the skeletal muscle sarcolemma and into the transverse tubules. Derangements in muscle electrical excitability cause myotonia or periodic paralysis. This chapter reviews the molecular genetic origins of these disorders and outlines the pathophysiological link between altered behavior of mutant channels and clinical phenotype.
