First case of a rare form of autosomal dominant axonal hereditary motor and sensory polyneuropathy caused by a mutation c.754C>T, p.Arg252Trp in the MORC2 gene with late onset (HMSN type 2Z)

Charcot-Marie-Tooth disease (CMT), also known as hereditary motor and sensory neuropathies (HMSN) is a group of inherited motor and sensory peripheral neuropathies and the most common inherited neuromuscular disorder. HMSN was first described as a clinical entity in 1886 by physicians Jean-Marie Charcot, Pierre Marie, and Howard Henry Tooth, who called it "progressive muscular atrophy." HMSN is heterogeneous in its clinical, electrophysiological, genetic, and pathological features. We present a 53-year-old man with a 20-year history of progressive weakness of the lower and upper limbs and an unsteady gait. On admission, physical examination revealed bilateral weakness and weakness of the distal muscles of the upper and lower limbs, pes planus, and elevated serum creatine phosphokinase (CPK). Electromyography showed axonal neuropathy affecting both the upper and lower limbs. Molecular genetic testing identified a pathogenic variant p.Arg252Trp in the MORC2 gene.Therefore, these clinical and genetic findings suggest a diagnosis of hereditary motor and sensory neuropathy type 2Z.