THIRD EDITION
Factsheet
Condition:
Leber hereditary optic neuropathy (LHON)
Inheritance:
Mitochondrial (maternal transmission)
Genetic Etiology:
Mutation in various mitochondrial genes involved in complex I of respiratory chain; the three most common mutations are G11778A in MT-ND4, T14484C in MT-ND6, and G3460A in MT-ND1.
Frequency:
Clinical disease about 1/30,000.
Clinical features:
LHON presents in young adults, particularly in males with subacute onset of blindness in one or both eyes. Vision progressively deteriorates, though some spontaneous improvement may occur.
Management:
Supportive care.
Genetic counseling:
Transmitted maternally, with affected individuals generally homoplasmic for mutation. There is a high rate of nonpenetrance, especially in females, for unknown reasons. Molecular genetic testing is available.