NDUFA13 and Leigh syndrome: From the 1990s, magnetic resonance imaging of the brain, specifically T2 hyperintensities variably involving the basal ganglia, midbrain, brainstem, cerebellum and spinal cord, in a compatible clinical context with evidence of mitochondrial dysfunction, came to supersede post-mortem brain examination in the diagnosis of Leigh syndrome.2 Brain imaging of the NDUFA13 deficient cohort revealed prominent involvement of the substantia nigra (11/12 cases) and bilateral optic nerve atrophy (8/12).