Ultrastructural studies of mitochondria in the peripheral nerves of CMT2A patients described abnormal mitochondrial aggregation in the distal part of axons [11, 20, 35] and corresponding impairment of the mitochondrial network and organization in the presence of MFN2 mutations [21, 36]. This evidence concerns the gene MFN2 and Charcot-Marie-Tooth disease type 2A1.