What is Charcot-Marie-Tooth Disease?
CMT is a peripheral neuropathy named after the three physicians who first described it; Jean-Martin Charcot, Pierre Marie (both from France) and Howard Henry Tooth of the United Kingdom. CMT is the most commonly inherited peripheral neuropathy.
A neuropathy is a condition that involves a problem or disfunction of the nerves. Peripheral refers to our peripheral nervous system (PNS) which consists of all of the nerves that branch off from the central nervous system (brain & spinal cord) and extend to the feet and hands. Along each nerve is an “insulator” called myelin, which surrounds, and is produced by a second cell type called a Schwann cell.
The PNS serves the essential function of transmitting instructions to and from the brain. This signaling regulates the function of muscles and can also measure sensation such as touch or heat. CMT is often referred to as a neuromuscular condition because failure of the nerves causes the malfunctioning of the muscles.
Peripheral Neuropathies result from damage to the nerve, or to the Schwann cell. The damage can be the result of illnesses such as diabetes or an infection, or result from the treatment of cancer patients with certain commonly used chemo-therapies. Patients who inherit the condition have a defect in the master code of DNA which causes the peripheral nerve to lose function. Peripheral Neuropathies of genetic origin are called Charcot-Marie Tooth (CMT) disorders, and are broadly classified as Type 1 or Type 2 depending on whether the cause is due to a mistake in a gene that normally contributes to a key function of either the Schwann or Nerve cell, respectively.
