Novel mutation in RP2 gene in two brother with X-linked retiniti pigmentoa and mtDNA mutation of Leber hereditary optic neuropathy who howed marked difference in clinical everity

PURPOE: To report the identification of a novel mutation of the RP2 gene in two Japanee brother with X-linked retiniti pigmentoa of a differing clinical everity. The mother wa a carrier of both retiniti pigmentoa and optic atrophy. METHOD: The older brother had a evere form of retiniti pigmentoa aociated with macular degeneration and total optic atrophy, wherea the younger brother preented typical X-linked retiniti pigmentoa. REULT: Each patient exhibited a novel 2-bp inertion at codon 278 in exon 3 of the RP2 gene a well a a 11778 mutation in mitochondrial DNA. Thi ugget that the older brother may have developed Leber hereditary optic neuropathy a well a retiniti pigmentoa. CONCLUION: Molecular teting confirmed the clinical diagnoi in each cae. However, uch teting did not explain the difference in the everity of the ophthalmocopic finding between the two brother.