Leber’s hereditary optic neuropathy: clinical and genetic analysis of Bulgarian patients

Leber’s hereditary optic neuropathy (LHON) is a rare maternally inherited disease caused by mutations in mitochondrial DNA (mtDNA) genes encoding subunits of complex I the respiratory chain. The most common causing LHON are G11778A, G3460A and T14484C, but there also several less mutations. presents as acute or subacute bilateral visual loss, usually affecting young males. aim this study was to assess clinical symptomatology genetic analysis Bulgarian patients with LHON. Twenty-two were diagnosed based on evaluation examination (17 males 5 females); 12 them previously reported, while 8 2 females newly diagnosed. A full neuroophthalmologic performed. Eight had family history LHON, 14 isolated cases. age at onset ranged from 3 43 years, acuity counting fingers 0.9. Genetic testing revealed various mutations, including mutation G3635A MT-ND1 five affected members one pedigree digenic inheritance G11778A T14484C three individuals different family. variant m.15988A > G gene MT-TP high level heteroplasmy found patient. In addition our These results suggest that entire mtDNA sequence recommended cases strong suspicion since new pathogenic variants being identified.