CMT is an inherited neurological disease characterized by the gradual degeneration of nerves which starts in the hands and feet and results in progressive numbness, muscle weakness and loss of function. Type X2 is an inherited defect of the X chromosome and affects males to a greater degree than females.
* High foot arch * Weak lower leg muscles * Wasted lower leg muscles * Areflexia * Weak foot muscles
Type X Charcot-Marie-Tooth disease is caused by a mutation in the GJB1 gene, and intermediate forms of the disorder are caused by an altered DNM2 or YARS gene.
* Patients usually have significant family history of CMT. This history varies, depending on the inheritance and penetrance pattern of the particular disorder. Spontaneous mutations also have been reported. * Slow progressing weakness beginning in the distal limb muscles, typically in the lower extremities before the upper extremities, generally is noted. A subgroup of patients with CMT 1A can present with proximal muscle wasting and weakness.