The clinical course and radiological changes observed in these patients were inconsistent with those reported as the most common causes of BSN and related pathogenesis, such as infantile BSN (20), BSN and progressive polyneuropathy (21), biotin-responsive basal ganglia disease (22), Leber's hereditary optic neuropathy and dystonia (23), MT-ATP6-related neuropathy, ataxia and retinitis pigmentosa syndrome (24), Hallervorden–Spatz syndrome (25), and Huntington's disease (10). Here, MT-ATP6 is linked to Leber hereditary optic neuropathy.