Charcot-Marie-Tooth disease (CMT) is a group of inherited disorders that affects the peripheral nervous system characterised by progressive muscle atrophy and loss of sensation in different parts of the body. Charcot-Marie-Tooth disease type 4A (CMT4A) is a subtype of the most frequent and severe form of the disease - Charcot-Marie-Tooth disease type 4 (CMT4). CMT4A is caused by variations in GDAP1 gene that may affect proper functioning of peripheral nerves.