[Familial hyperkalemic periodic paralysis: a brief review of the adult human skeletal muscle sodium channel and the application of LA-PCR to the SCN4A gene analysis].

Recent work has revealed that familial hyperkalemic periodic paralysis, paramyotonia congenita and other non-dystrophic myotonias result from point mutations in the gene encoding the alpha-subunit of the adult human skeletal muscle sodium channel (SCN4A). Sodium channel myotonias are a diverse group of skeletal muscle disorders that share a common pathophysiological mechanism: all are caused by impaired rapid inactivation of skeletal muscle sodium channel. Clinical studies, pharmacology, electrophysiology and molecular genetics have contributed to an elucidation of the genotype-phenotype correlation within these disorders. This article briefly reviews recent advances in our understanding of skeletal muscle sodium channel and sodium channel myotonias. The application of LA-PCR to the SCN4A gene analysis is also referred.