The ClC-1 channel is almost exclusively expressed in skeletal muscle where it has a dominant role in maintaining the membrane potential at rest and is important for repolarization of the skeletal muscle cells.nMutations in the ClC-1 gene result in myotonia congenita, a condition in which an increase in the excitability of skeletal muscle leads to repetitive action potentials, stiffness, and delayed relaxation. The disease can be either autosomal dominant (Thomsen's disease), or recessive (Becker's myotonia).
