Charcot-Marie-Tooth disease (CMT) also known as Charcot–Marie–Tooth neuropathy is a heterogeneous group of disorders characterized by distal muscle weakness and atrophy and loss of sensation in the feet and/or hands. Usually, the initial symptoms are foot deformities, such as high arches and hammertoes and “inverted champagne bottle” appearance of the lower parts of the legs. Weakness and muscle atrophy may occur in the hands as the disease progresses. Other symptoms of the disease may include hearing loss and scoliosis.
Prevalence of CMT hereditary neuropathy is about 1:2500.
Based on clinical manifestations and affected genes, CMT can be divided into types and subtypes. The most common form of CMT is Charcot-Marie-Tooth type 1A caused by duplication of or mutation in the PMP22 gene.
CMT neuropathy can be inherited in an autosomal dominant, autosomal recessive, or X-linked manner.
Indications for genetic testing:
1. Confirmation of clinical diagnosis
2. Carrier testing for at-risk family members
3. Genetic counseling