Charcot–Marie–Tooth disease (CMT), also known as Charcot–Marie–Tooth neuropathy, hereditary motor and sensory neuropathy (HMSN) and peroneal muscular atrophy (PMA) — is a genetically and clinically heterogeneous group of inherited disorders of the peripheral nervous system characterized by progressive loss of muscle tissue and touch sensation across various parts of the body. Currently incurable, this disease is one of the most common inherited neurological disorders affecting approximately 1 in 2,500 people  equating to approximately 23,000 people in the United Kingdom and 125,000 people in the USA.
CMT was previously classified as a subtype of muscular dystrophy.
Signs and symptoms
Symptoms of CMT usually begin in late childhood or early adulthood. Some people do not experience symptoms until their early thirties or forties. Usually, the initial symptom is foot drop early in the course of the disease. This can also cause claw toe, where the toes are always curled. Wasting of muscle tissue of the lower parts of the legs may give rise to a “stork leg” or “inverted bottle” appearance. Weakness in the hands and forearms occurs in many people later in life as the disease progresses.
Loss of touch sensation in the feet, ankles and legs, as well as in the hands, wrists and arms is characteristic in various types of the disease. Early and late onset forms occur with ‘on and off’ painful spasmodic muscular contractions that can be disabling when the disease activates. High arched feet (pes cavus) are classically associated with the disorder. Sensory and proprioceptive nerves in the hands and feet are often damaged, while pain nerves are left intact. Overuse of an affected hand or limb can activate symptoms including numbness, spasm, and painful cramping.
Symptoms and progression of the disease can vary. Breathing can be affected in some; so can hearing, vision, as well as the neck and shoulder muscles. Scoliosis is common. Hip sockets can be malformed. Gastrointestinal problems can be part of CMT, as can chewing, swallowing, and speaking (due to atrophy of vocal cords). A tremorcan develop as muscles waste. Pregnancy has been known to exacerbate CMT, as well as extreme emotional stress. Patients with CMT must avoid periods of prolonged immobility such as when recovering from a secondary injury as prolonged periods of limited mobility can drastically accelerate symptoms of CMT.
Neuropathic pain is often a symptom of CMT, though, like other symptoms of CMT, its presence and severity varies from case to case. For some people, pain can be significant to severe and interfere with daily life activities. However, pain is not experienced by all people with CMT. When pain is present as a symptom of CMT, it is comparable to that seen in other peripheral neuropathies, as well as Postherpetic neuralgia and Complex regional pain syndrome, among other diseases.
(Note: The information above is courtesy of Wikipedia)