Types of Charcot-Marie-Tooth

Types of CMT

Researchers have identified mutations in more than 100 unique genes that cause CMT, but the vast majority of people with CMT (90%) have one of four types: CMT1A, CMT1B, CMT2A or CMT1X.

CMT classification system

CMT classification uses numbers (1, 2, 3, 4, 6) to depict type and letters (A, B, C … ) to represent a subgroup within that type. An exception is type X (CMTX), which is passed down by X-linked inheritance.

The most common types are:

  • CMT1: Demyelinating neuropathies (the protective layer around the nerve, known as the myelin sheath, is damaged, so the nerve signals transmit very slowly) Read more…
  • CMT2: Axonal neuropathies (the axon is damaged, which leads to loss of the nerve signal) Read more…
  • CMTX: X-linked gene inheritance
  • CMT4: Recessive inheritance