MFN2 and Charcot-Marie-Tooth disease: Much like OPA1, defects in MFN2 cause a disturbance of mtDNA maintenance through impairment of mitochondrial network dynamics.66 Mutations in MFN2 are typically associated with Charcot-Marie-Tooth disease (CMT2A) and hereditary motor and sensory neuropathy (CMT with HMSN type VI).66