Charcot-Marie-Tooth Disease in Cyprus: Epidemiological, Clinical and Genetic Characteristics

Abstract

Background: Charcot-Marie-Tooth disease (CMT) is the most common inherited neuropathy. CMT is classified into 2 main subgroups: a demyelinating and an axonal type. Further subdivisions within these 2 main categories exist and intermediate forms have more recently been described. Inheritance can be autosomal dominant, recessive or X-linked. CMT is associated with more than 30 loci, and about 25 causative genes have been described thus far. Methods: We studied epidemiological, clinical and genetic characteristics of CMT in the Cypriot population. Results: The prevalence of CMT in Cyprus on January 15, 2009, is estimated to be 16 per 100,000. Thirty-three families and 8 sporadic patients were ascertained. CMT was demyelinating in 52%, axonal in 33% and intermediate in 15% of the patients. Thirteen families had PMP22 duplication, 3 families had the PMP22 S22F mutation, 4 families had GJB1/Cx32 mutations, 2 families had different MPZ mutations, 1 of them novel, and 2 families had different MFN2 mutations. Nine families and 8 sporadic patients were excluded from the common CMT genes. Conclusion: The most frequent CMT mutation worldwide, the PMP22 duplication, is also the most frequent CMT mutation in the Cypriot population. Five out of the 8 other mutations are novel, not reported in other populations.

Identification of a Location at Chromosome 19p in a Big Chinese Family with Charcot-Marie-Tooth Disease

“…CMT is also known as hereditary motor and sensory neuropathy (HMSN), because it also affects the motor and sensory nerves. Variable ages of onset and progressive distal muscle weakness and atrophy are the main clinical characteristics, usually starting from the lower limbs and subsequently affecting the upper extremities [4]. The most typical features of the disease are gradual atrophy of distal muscles of the feet and legs, and the thin legs have been likened to an "inverted champagne bottle".…”

Case Report A novel mutation of the MFN2 gene in a Chinese family with Charcot-Marie-Tooth disease

“…The clinical features are a variable age of onset of progressive distal muscle weakness and atrophy, starting in the lower limbs and subsequently affecting the upper extremities (Nicolaou et al, 2010). Point mutations in the mitofusin 2 (MFN2) gene are some of the most common causes of CMT.…”

The Role of Gap Junctions in Charcot-Marie-Tooth Disease

“…The X-linked form of CMT (CMT1X) is the second most common form among all CMT patients with a frequency of 7-18% (average 12% internationally) (Nicolaou et al, 2010;Braathen et al, 2011). CMT1X is caused by Ͼ400 different mutations in the GJB1 gene that encodes the gap junction (GJ) protein connexin32 (Cx32).…”