Charcot-Marie-Tooth disease type 4A

GDAP1-related hereditary motor and sensory neuropathy (GDAP1-HMSN) is a peripheral neuropathy (also known as a subtype of Charcot-Marie-Tooth disease) that typically affects the lower extremities earlier and more severely than the upper extremities. As the neuropathy progresses, the distal upper extremities also become severely affected. Proximal muscles can also become weak. Age at onset ranges from infancy to early childhood. In most cases, disease progression causes disabilities within the first or second decade of life. At the end of the second decade, most individuals are wheelchair bound. Disease progression varies considerably even within the same family. The neuropathy can be either of the demyelinating type with reduced nerve conduction velocities or the axonal type with normal nerve conduction velocities. Vocal cord paresis is common. Intelligence is normal. Life expectancy is usually normal, but on occasion may be reduced because of secondary complications.

GeneReviews