By contrast, the homoplasmic or near homoplasmic mutations often manifest single organ or tissues, including Leber hereditary optic neuropathy (LHON)-associated ND4 11778G > A, ND1 3460G > A, and ND6 14484T > C [22], deafness-linked 12S rRNA 1555A > G and 1494C > T mutations [23, 24]. This evidence concerns the gene MT-ND4 and Leber hereditary optic neuropathy.