Charcot-Marie-Tooth disease: genetic subtypes in the Sardinian population

Abstract

Charcot-Marie-Tooth disease (CMT) is characterised by great variability of genetic subtypes. This study aimed to assess the genetic subtypes of CMT disease in the Sardinian population. Genetic screening was performed for CMT cases (CMT1, CMT2, and hereditary neuropathy with susceptibility to pressure palsies [HNPP]). A total of 1,043 subjects (119 index cases) were evaluated. In CMT1 index cases (69/119; 58%), PMP22 duplication at 17p11.2 was the most frequent genetic diagnosis (60/69; 87%), followed by mutations in the GJB1 gene (5/69; 7.2%), in the SH3TC2 gene (3/69; 4.4%) and PMP22 Gly107Val point mutation (1/69; 1.4%). The CMT2 group (24/119; 20.1%) comprised 10/24 (41.6%) patients carrying MPZ gene Ser44Phe mutation, 6/24 (25%) with mutations in MFN2 and HSPB1, and 1/24 (4.2%) in GJB1 and LRSAM1. In the HNPP group (26/119; 21.9%), the majority of patients reported the PMP22 deletion (25/26; 96.2%). Further studies are needed to comprehend the overall picture of the disease in Mediterranean area.

Keywords: Charcot–Marie–Tooth disease; Epidemiology; Genetic subtypes; Hereditary neuropathy with susceptibility to pressure palsies; Mediterranean area; Sardinian population.