Abstract: Objective To report the mutation ratio, mutation feature and corresponding clinical manifestations of Leber hereditary optic neuropathy(LHON) in Chinese patients with suspected hereditary optic atrophy. Design Retrospective case series. Participants Nine hundred and nine probands who have been suspected as LHON from 2006 to 2014 collected at our laboratory. Methods Sixteen primary LHON-causing mtDNA mutations were screened by PCR-based sequencing methods for all participants and some family members. The clinical features of LHON patients were recorded. Main Outcome Measures mtDNA mutation family medical history, visual acuity and fundus photography. Results Molecular defect in 432 (47.52%) of the 909 probands screened was detected. Among these, 369 patients (85.42%) were caused by m.11778G>A(294/432, 68.06%), m.14484T>C(58/432, 13.43%) or m.3460G>A(17/432, 3.94%). And 10 rare primary mtDNA mutation (m.3635G>A, m.3733G>A, m.3736G>A, m.3866T>C, m.4171C>A, m.10680G>A, m.11696A>G, m.14459G>A, m.14482C>G, m.T14502T>C) were found in 44 patients(10.18%). The other 19 (4.40%) patients were carrying two primary mtDNA mutations. The mean onset age of visual loss was 18.53±9.31 years (ranging from 3-66 years). The mean logMAR visual acuity for the probands carrying LHON-causing mtDNA mutations was 1.36±0.68. Conclusion LHON is a major type of Chinese hereditary optic atrophy. It is important to perform a mtDNA gene test for patients with unexplained decreased visual acuity. The mutation frequency of m.3460G>A is low in Chinese. (Ophthalmol CHN, 2015, 24: 85-89)

Key words: Leber hereditary optic neuropathy, optic atrophy, mtDNA mutations