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Dominant optic atrophy and Leber hereditary optic neuropathy are uncommon, inherited disorders that damage the optic nerve, causing vision loss.
Causes
Dominant optic atrophy and Leber hereditary optic neuropathy are inherited disorders caused by abnormal genes. Both disorders are uncommon, particularly Leber hereditary optic neuropathy.
Dominant optic atrophy is inherited from the mother or father as a dominant gene (see Genetics: Inheritance Patterns), meaning that only one copy of the gene is required for the disorder to develop.
Leber hereditary optic neuropathy is inherited through the mother only because the abnormal genes seem to be located in the mitochondria. Mitochondria are structures in cells that provide energy for the cell and have their own internal genes that are inherited from only the mother (see Genetics: Abnormal Mitochondrial Genes). Leber hereditary optic neuropathy is more common among men.
Symptoms
In dominant optic atrophy, vision loss begins before the age of 10 years. Some people have vertigo (a false sensation of moving or spinning) or hearing loss. In Leber hereditary optic neuropathy, vision loss begins between the ages of 15 and 35. Some people have abnormal heart conduction or nervous system function.
Diagnosis
Diagnosis is by a doctor's evaluation. Testing can identify some of the abnormal genes responsible for the disorders, but not all.
Treatment
There is no effective treatment. Limiting consumption of alcohol, which may affect the mitochondria, and not using tobacco products may help slow the rate of vision loss. Magnifiers, large-print devices, and talking watches may help people with loss of vision. Genetic counseling should be considered.
Last full review/revision November 2012 by James Garrity, MD
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