MFN2 and autosomal dominant optic atrophy: Mutations in Mfn2 cause the Charcot-Marie-Tooth type 2A (CMT2A) [14], one of the most common hereditary neuropathies, and mutations in OPA1 are the predominant cause of autosomal dominant optic atrophy (DOA), a heritable form of optic neuropathy [15, 16].