Charcot-Marie-Tooth (CMT) disease or hereditary motor and sensory neuropathy is the most frequent inherited neuromuscular disease, with a prevalence of 1/2 500 individuals (Suter and Sherer, 2003).
CMT is a complex disorder at the molecular level, with at least 1 000 genetic variants associated with about 80 genes (Timmerman et al., 2014). In the wide series described, molecular alteration is identified in 60%-70% of patients (80% of demyelinating forms and 25% of axonal forms) (Rossor et al., 2015). Approximately 90% of alterations are found in genes PMP22, MPZ, GJB1, and MFN2 (DiVicenzo et al., 2015), although this number varies among populations and is particularly reduced in regions with a high prevalence of recessive inheritance forms. 40%-50% of CMT cases are type 1 (CMT1, demyelinating form), of which 70-80% are caused by a duplication of a region of about 1.5 Mb in 17p12 containing the PMP22 gene (CMT1A).
Hereditary motor neuropathy (HMN) comprises 10% of all hereditary neuropathies, with a diagnosis rate of 20%-32% (Bansagi et al., 2017).