| Charcot-Marie-Tooth disease type 4D (CMT4D) is a severe form of Charcot-Marie-Tooth disease type 4, a demyelinating hereditary motor and sensory neuropathy. Main features described as gait disorder manifesting in the first decade of life, followed by upper limb involvement observed in the second decade and sensorineural deafness usually manifesting in the second or third decade of life. CMT4D was first reported in the Bulgarian Romani community of Lom and to date, has mainly been associated with the Roma population. CMT4D is caused by a single ancestral mutation (p.R148X) in the NDRG1 gene (8q24) coding for the NDRG1 protein that has a role in the peripheral nervous system, possibly in Schwann cell signaling necessary for axonal survival. Transmission is autosomal recessive. |
