Charcot-Marie-Tooth disease, type 2A2

Charcot-Marie-Tooth disease constitutes a clinically and genetically heterogeneous group of hereditary motor and sensory neuropathies. On the basis of electrophysiologic criteria, CMT is divided into 2 major types: type 1, the demyelinating form, characterized by a slow motor median nerve conduction velocity (NCV) (less than 38 m/s), and type 2, the axonal form, with a normal or slightly reduced NCV. Distal hereditary motor neuropathy (dHMN), also known as spinal CMT, is a third type of CMT characterized by normal motor and sensory NCV and degeneration of spinal cord anterior horn cells. See CMT1B ({118200}) and CMT1A ({118220}) for descriptions of autosomal dominant slow nerve conduction types of Charcot-Marie-Tooth disease. See CMT4A ({214400}) and CMTX1 ({302800}) for autosomal recessive and X-linked forms of Charcot-Marie-Tooth disease, respectively. For a discussion of genetic heterogeneity of CMT type 2, see {118210}.