The disease most frequently affects young males, with a mean age of onset in the mid-20s, although the range is extremely broad.1 Common features of the acute phase include peripapillary microangiopathy and optic disc atrophy.2 The classic LHON phenotype is associated to three mtDNA mutations: G3460A, G11778A, and T14484C, in the ND1, ND4 and ND6 genes, respectively, all encoding for complex I subunits of the mitochondrial respiratory chain. The gene discussed is MT-ND4; the disease is optic atrophy.