New mutation in periaxin gene causing Charcot Marie Tooth disease in a Puerto Rican young male.

Charcot-Marie-Tooth (CMT) disease is an inherited peripheral neuropathy caused by mutations in more than 30 different genes. One of the genes encodes for periaxin (PRX) protein, which is required for the maintenance of peripheral nerve myelin. Individuals with PRX gene mutations have been described to present early-onset, autosomal recessive, demyelinating CMT disease or CMT4F subtype. Only 23 mutations involving the PRX gene have been reported in patients throughout the world. We describe a case of a Puerto Rican adolescent with history, neurologic examination, electromyographic data, and laboratory tests consistent with CMT4F. Genetic analysis of this individual showed a heterozygous transversion resulting in amino acid change from arginine to glycine in the PRX gene, suggesting CMT4F. We report this novel PRX mutation to expand the clinical spectrum of CMT disease.