MedGen

Leber hereditary optic neuropathy (LHON) typically presents in young adults as bilateral, painless, subacute visual failure. The peak age of onset in LHON is in the second and third decades of life, with 90% of those who lose their vision doing so before age 50 years. Very rarely, individuals first manifest LHON in the seventh and eighth decades of life. Males are four to five times more likely to be affected than females, but neither sex nor mutational status significantly influences the timing and severity of the initial visual loss. Neurologic abnormalities such as postural tremor, peripheral neuropathy, nonspecific myopathy, and movement disorders have been reported to be more common in individuals with LHON than in the general population. Some individuals with LHON, usually women, may also develop a multiple sclerosis-like illness. [from GeneReviews]

Leber optic atrophy, also known as Leber hereditary optic atrophy (LHON; 535000), is characterized by bilateral, painless, subacute central vision loss in young adults resulting from primary degeneration of retinal ganglion cells (RGCs) accompanied by ascending optic atrophy (summary by Yu et al., 2020). Variation in mitochondrial DNA (mtDNA) contributes to the pathogenesis of the disease. Modifier of Leber optic atrophy (LOAM) exhibits increased penetrance and earlier age of onset compared to Leber optic atrophy caused by the LHON11778A mutation in the MTND4 gene (516003.0001) alone, due to the action of mutation in PRICKLE3 as a modifier of expression of the disease. For a general description and discussion of genetic heterogeneity of Leber optic atrophy, see 535000. [from OMIM]