MODELIZATION OF MOTOR-NERVE CONDUCTION VELOCITIES FOR CHARCOT-MARIE-TOOTH (TYPE-1) PATIENTS

Charcot-Marie-Tooth (CMT) type-1 (CMT1) neuropathy is characterized by peripheral nerve demyelination and has been divided into several subt ypes. The most frequent among these, subtype 1A, is related to a micro duplication of the region p11.2 of chromosome 17. This region contains the PMP-22 gene which is involved in peripheral nerve myelination. Si nce motor nerve conduction velocity (MNCV) is closely related to nerve myelination, we compared type-IA patient MNCVs versus non-A CMT1 pati ent MNCVs, in 57 CMT 1A patients and 21 non-A type-1 patients, Patient s with the 17p11.2 duplication have MNCVs that are significantly more reduced (about 20 m/s) compared to patients without the 17p11.2 duplic ation (about 30 m/s). This study also permits a model of the MNCV in t he median nerve (MedMNCV) of CMT1 patients, with age, gender and molec ular status as parameters, Furthermore, in order to help clinicians to diagnose subtypes of CMT1 patients, the probability for type 1A is mo deled as a function of MedMNCV only.