Diagnostic potential of mitochondrial DNA assessment in patients with optic neuropathy.

OBJECTIVE

To study the primary mutations of mitochondrial DNA (mtDNA) associated with Leber's hereditary optic neuropathy (LHON) in patients with optic neuropathy.

METHODS

Seventy-nine patients with a variety of bilateral optic neuropathies were examined. Mutations at np3460, np11,778 and np14,484 of mtDNA were tested by PCR-restriction detection in peripheral blood DNA from 16 cases of clinically probable LHON, 44 cases of possible LHON, 2 cases of alcohol amblyopia, 4 cases of multiple sclerosis, 5 cases of autosomal dominant optic atrophy, 4 cases of primary open-angle glaucoma, 3 cases of spinocerebellar degeneration, and 1 case of ethambutol-induced optic neuropathy.

RESULTS

The mutation at np11778 was identified in 31 cases (39.2%) to establish LHON, which consisted of: all 16 of clinically probable LHON cases, 13 cases (29.5%) of possible LHON, and 2 cases of alcohol amblyopia. The remaining 48 cases were negative for mtDNA mutations at np3460, np11 778, and np14,484.

CONCLUSIONS

Assessment of mtDNA provides a useful diagnostic aid in the definition and exclusion of LHON, in particular family history-negative, otherwise undefined bilateral optic nerve inflammatory disease.