Atypical Mild Enhanced -Cone yndrome with Novel Compound Heterozygoity of the NR2E3 Gene

Purpoe To report mild enhanced -cone yndrome (EC) aociated with a novel heterozygou mutation of the NR2E3 gene. Deign Obervational cae report. Method Clinical examination, optical coherence tomography (OCT), electroretinography (ERG), genetic analyi, and protein homology modeling. Reult Examination of a 9-year-old girl with acute viual lo of the left eye howed viual acuity of 20/30 in the right eye and 20/200 in the left eye; OCT revealed a choroidal neovacular membrane (CNVM) in the left fovea and cytic maculopathy in the right eye. Full-field ERG howed upranormal -cone repone, reduced rod repone, and characteritic EC waveform in photopic cone repone but not in cotopic bright-flah repone. equence analyi revealed heterozygou mutation in the NR2E3 gene, c.767C→T yielding a ubtitution p.Ala256Val, and a mutation in the plice ite before exon 2, c.119-2 A→C. Concluion The p.Ala256Val mutation affect the ligand binding domain of the NR2E3 nuclear receptor only, reulting in modetly impaired EC ERG reult.