Optic atrophy refers to the death of the retinal ganglion cell axons that comprise the optic nerve. Optic atrophy is an end stage that arises from myriad causes of optic nerve damage anywhere along the path from the retina to the lateral geniculate. Since the optic nerve transmits retinal information to the brain, optic atrophy is associated with vision loss. Optic atrophy is somewhat of a misnomer as atrophy implies disuse and optic nerve damage is better termed optic neuropathy. [http://eyewiki.aao.org/Optic_Atrophy]

Optic atrophy-12 (OPA12) is an autosomal dominant neurologic disorder characterized by slowly progressive visual impairment with onset usually in the first decade, although later onset has been reported. Affected individuals have impaired color vision, photophobia, pale optic discs, optic nerve atrophy, and decreased thickness of the retinal nerve fiber layer. Some patients may exhibit additional neurologic features, including impaired intellectual development, dystonia, movement disorders, or ataxia (summary by Caporali et al., 2020; pubmed:32219868). [from MIM:618977; 2021.01.11]

Optic atrophy-12 (OPA12) is caused by heterozygous mutation in the AFG3L2 gene. [from MIM:618977; 2021.01.11]

AFG3L2 is the catalytic subunit of the m-AAA protease, an ATP-dependent proteolytic complex of the mitochondrial inner membrane that degrades misfolded proteins and regulates ribosome assembly (summary by Koppen et al., 2007; pubmed:17101804). [from MIM:604581; 2021.01.11]