Clinical Phenotype in an Early-Onset French Pediatric Population: Charcot–Marie–Tooth's Disease Type 2A

Abstract

Charcot–Marie–Tooth's disease type 2A (MCT2A), induced by mutation of the mitofusin 2 (MFN2) gene represents the main cause of MCT2. The aim of this study is to provide details of the clinical and electromyographic phenotype of MCT2A in a pediatric population. We conducted a French multicenter retrospective study, including all children with a genetic diagnosis of MCT2A. Thirteen MCT2A children were included with a beginning of symptoms before the age of 10 years (“early-onset group”). We report two new mutations: c.1070 A → T (p.Lys357.Met) and c.280 C → G (p.Arg94Gly). The evolution of the disease is marked by a fast worsening for three patients with loss of motor autonomy, while the evolution is relatively stable for eight patients. The group of early-onset MCT2A seems more heterogeneous than previously described, with a nonconstant severe phenotype.

Keywords

neuropathy - Charcot–Marie–Tooth - mitofusin - child - phenotype

^* These authors contributed equally to this work.

Publikationsverlauf

Eingereicht: 17. Februar 2020

Angenommen: 10. Juli 2020

Artikel online veröffentlicht:
12. Februar 2021

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