Leber hereditary optic neuropathy (LHON) is the typical single organ involvement mitochondrial disorder caused by mtDNA point mutations such as genevariation on m.3460G → A MT-ND1, m.11778G → A MT-ND4, and m.14484 T → C MT-ND6. The gene discussed is MT-ND6; the disease is Leber hereditary optic neuropathy.