Charcot-Marie-Tooth disease (CMT), known also as Hereditary Motor and Sensory Neuropathy (HMSN), Hereditary Sensorimotor Neuropathy (HSMN), or Peroneal Muscular Atrophy, is a heterogeneous inherited disorder of nerves (neuropathy) that is characterized by loss of muscle tissue and touch sensation, predominantly in the feet and legs but also in the hands and arms in the advanced stages of disease. Presently incurable, this disease is one of the most common inherited neurological disorders, with 37 in 100,000 affected. The disorder is caused by the absence of proteins that are essential for normal function of the nerves due to errors in the gene coding molecules.

The absence of these chemical substances gives rise to dysfunction either in the axon or the myelin sheath of the nerve cell. Most of the mutations identified result in disrupted myelin production, however a small proportion of mutations occur in gene MFN2, which doesn't seem to have anything to do with myelin. Instead MFN2 controls behaviour of mitochondria.

Recent research showed that the mutated MFN2 causes mitochondria to form large clusters. In nerve cells these large clusters of mitochondria failed to travel down the axon towards the synapses. It is suggested these mitochondria clots make the synapses fail, resulting in CMT disease.

The different classes of this disorder have been divided into the primary demyelinating neuropathies (CMT1, CMT3, and CMT4) and the primary axonal neuropathies (CMT2). Recent studies, however, show that the pathologies of these two classes are frequently intermingled, due to the dependence and close cellular interaction of Schwann cells and neurons. Schwann cells are responsible for myelin formation, enwrapping neural axons with their plasma membranes in a process called “myelination”.

Similar to 0 things you like: