This gene encodes a major structural protein of peripheral myelin. Mutations in this gene result in the autosomal dominant form of Charcot-Marie-Tooth disease type 1 and other polyneuropathies. The myelin sheath is a multi-layered membrane, unique to the nervous system, that functions as an insulator to greatly increase the velocity of axonal impulse conduction. The P0 glycoprotein, absent in the central nervous system,[1] is a major component of the myelin sheath in peripheral nerves. It comprises a large extracellular N-terminal domain, a single transmembrane (TM) region, and a smaller positively charged intracellular domain.