Indeed, dozens of different pathological MFN2 mutations cause neuronal rather than cardiac pathology, manifested as Charcot–Marie–Tooth disease type 2A (CMT2A) (Züchner et al., 2004) or optic degeneration (Züchner et al., 2006). Here, MFN2 is linked to Charcot-Marie-Tooth disease type 2A1.