MT-ATP6 and maternally-inherited Leigh syndrome: Of these syndromes, only the complex ataxia-related syndrome described by Kytövouri is caused by a unique mutation of MT-ATP6, m.8561C>G (p.P12S) [12], which was formerly not associated with maternally inherited Leigh syndrome (MILS), or neuropathy, ataxia, and retinitis pigmentosa (NARP) syndrome [3].