Definition:

Giant axonal neuropathy is a disorder that shows giant axons, caused by accumulation of neurofilaments. Giant axonal neuropathy 1 (GAN1) is autosomal recessively inherited and caused by mutations in GAN (gigaxonin). GAN1 is characterized by an early onset severe peripheral neuropathy, varying central nervous system involvement and strikingly frizzly hair. Giant axonal neuropathy-2 (GAN2) is an autosomal dominant disorder, caused by mutations in DCAF8. GAN2 is characterized by distal sensory impairment and lower extremity muscle weakness and atrophy after the second decade.