Charcot Marie Tooth disease is a genetic disorder of the nerves that affects 1 in 2,500 people in the United States. People with this condition experience muscle weakness, especially in the arms and legs. The condition affects the peripheral nerves. These nerves are located outside the central nervous system (CNS). They control the muscles and transmit the data from the arms and legs to the brain so that a person can feel the touch.1
Charcot Marie Tooth is perennial muscle atrophy or hereditary motor and sensory neuropathy. The name comes from the doctors who first described it: Jean Charcot, Pierre Marie, and Howard Henry Tooth. The condition is progressive, which means that symptoms gradually worsen over time, but most people with Charcot Marie Tooth have a normal life span. It affects men and women alike and all ethnic groups. Charcot Marie Tooth is a congenital disease, meaning it is present at birth.2
Is Charcot Marie Tooth A Serious Disease?
Charcot Marie Tooth is a hereditary disease, so people with close family members with Charcot Marie Tooth have a higher risk of developing it. The disorder affects the peripheral nerves. A peripheral nerve consists of two major parts, the axon, which is the interior of the nerve, and the myelin sheath, which is the protective layer around the axon.
Charcot Marie Tooth may affect the axon, myelin sheath or both, depending on the type of Charcot Marie Tooth. CMT 1 for about 1 in 3 cases. In CMT1, mutated or defective genes cause the myelin sheath to disintegrate. When the myelin sheath disappears, the axon eventually becomes damaged and the patient’s muscles receive no clear message from the brain. This leads to muscle weakness and loss of sensation or numbness.
- In Charcot Marie Tooth 2, the defective gene directly affects the axons. The signals are not transmitted strong enough to activate muscles and senses, leaving patients with weaker muscles and a worse sense of touch or numbness. CMT 2 accounts for about 17% of the cases.
- Charcot Marie Tooth 3 is rare and it damages to the myelin sheath causing severe muscle weakness, and the sense of touch is also severely impaired. Symptoms can occur in children.
- Charcot Marie Tooth 4 is a rare disease that affects the myelin sheath. Symptoms usually appear during childhood, and patients often require a wheelchair.
- Charcot Marie Tooth X is related to mutations in an X chromosome mutation. It is more common in men. A woman with CMT X will have very mild symptoms.4,6
Can Charcot Marie Tooth Be Reversed?
Charcot Marie Tooth disease is a difficult syndrome to cope with. The disease is generally not life-threatening or decreased life expectancy. But in many cases, the quality of life affects largely. Early diagnosis and adherence to remedial measure and management therapies offer better prognosis and life quality. It is an incurable disease with symptomatic treatment options providing relief and better coping ability.
The condition is caused by one or more defective genes. In most cases, you inherit the defective genes from one or both parents. The defects interfere with the function and structure of your peripheral nerve sheaths and axons. These are the insulating layers around your nerves.
In some rare cases, people are spontaneously born with Charcot Marie Tooth without inheriting a defective gene from their parents. There are five main types of Charcot Marie Tooth, and each has its own cause3:
Charcot Marie Tooth 1 is often caused by a duplication of a gene on chromosome 17. This gene controls the production of the protective myelin sheath of your nerves. CMT1 is also caused by other genetic defects.
Charcot Marie Tooth 2 results from a defect in the axon of your peripheral nerve cells. This is caused by a defect in your mitofusin 2 gene.
Charcot Marie Tooth 3, also called Dejerine-Sottas disease, is caused by a mutation in your P0 or PMP-22 gene. This type of CMT is rare.
Charcot Marie Tooth 4 is caused by multiple gene mutations. These genes include GDAP1, MTMR13, MTMR2, SH3TC2, NDG1, EGR2, PRX, FDG4 and FIG4.
Charcot Marie Tooth X is caused by a point mutation in the connexin 32 protein on your X chromosome.
CMT1 is the most common type of CMT. All types of Charcot Marie Tooth weaken the signals that travel from nerves in your extremities to your brain.
- Barreto LCLS, Oliveira FS, Nunes PS, et al. Epidemiologic study of Charcot-Marie-Tooth disease: a systematic review. Neuroepidemiology. 2016;46(3):157-165.
- Khadilkar SV, Yadav RS, Patel BA. Charcot–Marie–Tooth Disease. Neuromuscular Disorders: Springer; 2018:421-439.
- Pareyson D, Marchesi C. Diagnosis, natural history, and management of Charcot–Marie–Tooth disease. The Lancet Neurology. 2009;8(7):654-667.
- Rossor AM, Polke JM, Houlden H, Reilly MM. Clinical implications of genetic advances in Charcot–Marie–Tooth disease. Nature Reviews Neurology. 2013;9(10):562.
- Arnold A, McEntagart M, Younger DS. Psychosocial issues that face patients with Charcot‐Marie‐Tooth disease: the role of genetic counseling. Journal of genetic counseling. 2005;14(4):307-318.
- Abresch RT, Carter GT, Jensen MP, Kilmer DD. Assessment of pain and health-related quality of life in slowly progressive neuromuscular disease. American Journal of Hospice and Palliative Medicine®. 2002;19(1):39-48.
Also Read:
- Charcot Marie Tooth Disease or CMT: Symptoms, Causes, Types, Treatment
- Is Charcot Foot The Same As Charcot Marie Tooth?
- Is Charcot Marie Tooth Disease Painful & Can CMT Skip A Generation?
- Classification Of Charcot Marie Tooth Disease
- How Common Is Charcot Marie Tooth Or Is It A Rare Disease?
- Is Charcot Marie Tooth Disease A Disability?
- Is There A Surgery For Charcot Marie Tooth Disease?
