ACO2 and Leber hereditary optic neuropathy: In some disorders both optic neuropathy and retinopathy coexist: an ACO2 mutation has been linked to optic atrophy, vessel narrowing, and retinal degeneration [52], and patients with pathogenic missense variants in SSBP1 often have optic atrophy, vessel narrowing, and pigmented retinal changes, although there is wide variation [53].