What causes Charcot-Marie-Tooth disease type 2F ?
What causes Charcot-Marie-Tooth disease type 2F? Charcot-Marie-Tooth disease type 2F (CMT2F) is caused by mutations in the HSPB1 gene. This gene provides instructions for making a protein (heat shock protein beta-1) which helps protect cells under adverse conditions. Heat shock proteins appear to be involved in activities such as cell movement, stabilizing the cell's framework, folding and stabilizing new proteins, repairing damaged proteins, and muscle contraction. Heat shock protein beta-1 is particularly abundant in nerve and muscle cells. In nerve cells, it helps to organize a network of threads that maintain the diameter of axons (neurofilaments), which are needed to transmit nerve impulses efficiently. It is unclear exactly how HSPB1 mutations lead to the axon abnormalities characteristic of CMT2F. Researchers suggest that mutations lead to an altered protein which clusters together and interferes with nerve cell function. Another possibility is that the altered protein disrupts the assembly of neurofilaments, which in turn may impair the transmission of nerve impulses.