Giant Axonal Neuropathy (gan) Detailed Information
Giant axonal neuropathy (GAN) is a degenerative disorder of the peripheral nerves that is inherited as an autosomal recessive attribute, presenting in early childhood and progressing to death, usually by late adolescence. Giant axonal neuropathy is caused by mutations in the GAN gene, which offers instructions for making a protein called gigaxonin. Some GAN mutations alter the shape of the protein, affecting how it binds to other proteins to form a functional complex. Other mutations prevent cells from producing any gigaxonin protein. The protein is necessary for normal nerve function because it forms neurofilaments.
Neurofilaments make up a structural framework that assists to define the shape and size of the neurons. Giant axonal neuropathy generally shows in babyhood or early childhood. It progresses gradually as neuronal injury becomes more severe. Signs of giant axonal neuropathy usually start in the peripheral nervous system, which governs movement and sensation in the arms, legs, and other parts of the body. Most individuals with this disorder first have problems with walking. Later they may lose sensation, coordination, strength, and reflexes in their limbs. Hearing and visual problems may also arise.
Really kinky hair (as evaluated to others in the family) is characteristic of giant axonal neuropathy, occurring in almost all affected people. As the disorder progresses, the brain and spinal cord (central nervous system) may become involved, causing a gradual decline in mental function, loss of manage of body movement, and seizures. Gigaxonin is involved in a cellular function that kills and gets rid of excess or damaged proteins using a mechanism called the ubiquitin-proteasome system. Neurons without functional gigaxonin add surplus neurofilaments in the axon, causing the axons to become distended.
Here is a link to more information about the genetics of Giant Axonal Neuropathy that was prepared by our genetic counselor and which has links to some useful resources for those dealing with this condition: http://www.accessdna.com/condition/Giant_Axonal_Neuropathy/163. There is also a phone number listed if you need to speak to a genetic counselor by phone. I hope it helps. Thanks, AccessDNA