| Prognosis | Variable, but generally more progressive than dominant forms; many patients require wheelchair by the second or third decade |
| Age of onset | Usually in the first decade of life; many children present with delayed motor milestones or difficulty walking |
| Severity | Often more disabling than CMT1, with earlier wheelchair dependence in some subtypes |
| Geographic distribution | More prevalent in populations with higher rates of consanguinity (Mediterranean, Middle Eastern, North African populations) due to recessive inheritance |
| CMT4A (GDAP1) | Ganglioside-induced differentiation-associated protein 1 mutations; both demyelinating and axonal forms; associated with vocal cord paresis |
| CMT4B1/B2 (MTMR2/MTMR13) | Myotubularin-related proteins; distinctive "focally folded" myelin sheaths on nerve biopsy |
| CMT4C (SH3TC2) | SH3 domain and tetratricopeptide repeats 2; most common CMT4 subtype; scoliosis is a prominent feature |
| CMT4F (PRX) | Periaxin; severe sensory loss with sensory ataxia |
| CMT4J (FIG4) | Phosphoinositide phosphatase; rapidly progressive course |
| Clinical features | Prominent scoliosis, foot deformities, distal limb weakness, and sensory loss; cranial nerve involvement may occur in some subtypes |
| NCV values | Intermediate range (25–45 m/s in males), which can complicate classification. Females typically show higher NCV values than affected males |
| Other CMTX types | CMTX2–CMTX6 are rare subtypes caused by mutations in AIFM1, GJB3, and other X-linked genes |
| Databases | OMIMOrphanetClinicalTrialsPubMed |
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