MedGen

Charcot-Marie-Tooth disease type 4 (CMT4) belongs to the genetically heterogeneous group of CMT peripheral sensorimotor polyneuropathy diseases. Type 4 is less common and often limited to certain ethnic groups. Patients present with the typical CMT phenotype along with typical features of progressive, distally accentuated weakness and atrophy of muscles innervated by the peroneal nerve in the lower limbs, followed by weakness and atrophy of hands, sensory loss, and characteristic foot abnormalities. [from SNOMEDCT_US]

A subtype of Charcot-Marie-Tooth type 4 with characteristics of childhood onset of slowly progressing, demyelinating sensorimotor neuropathy, focally folded myelin sheaths in nerve biopsy, reduced nerve conduction velocities and the typical Charcot-Marie-Tooth phenotype (i.e. distal muscle weakness and atrophy, and sensory loss). There is evidence this disease is caused by homozygous or compound heterozygous mutation in the SBF1 gene on chromosome 22q. [from SNOMEDCT_US]