Lam Byron L, Goldberg Jeffrey L, Hartley Kristen L, Stone Edwin M, Liu Mu
Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida 33136, USA.
Am J Ophthalmol. 2007 Jul;144(1):157-9. doi: 10.1016/j.ajo.2007.03.012.
To report mild enhanced s-cone syndrome (ESCS) associated with a novel heterozygous mutation of the NR2E3 gene.
Observational case report.
Clinical examination, optical coherence tomography (OCT), electroretinography (ERG), genetic analysis, and protein homology modeling.
Examination of a 9-year-old girl with acute visual loss of the left eye showed visual acuity of 20/30 in the right eye and 20/200 in the left eye; OCT revealed a choroidal neovascular membrane (CNVM) in the left fovea and cystic maculopathy in the right eye. Full-field ERG showed supranormal s-cone responses, reduced rod response, and characteristic ESCS waveform in photopic cone response but not in scotopic bright-flash response. Sequence analysis revealed heterozygous mutations in the NR2E3 gene, c.767C-->T yielding a substitution p.Ala256Val, and a mutation in the splice site before exon 2, c.119-2 A-->C.
The p.Ala256Val mutation affects the ligand binding domain of the NR2E3 nuclear receptor only, resulting in modestly impaired ESCS ERG results.
报告与NR2E3基因新的杂合突变相关的轻度增强型视锥细胞综合征（ESCS）。
观察性病例报告。
临床检查、光学相干断层扫描（OCT）、视网膜电图（ERG）、基因分析和蛋白质同源性建模。
对一名9岁左眼急性视力丧失的女孩进行检查，结果显示右眼视力为20/30，左眼视力为20/200；OCT显示左眼黄斑中心凹有脉络膜新生血管膜（CNVM），右眼有黄斑囊样病变。全视野ERG显示超常的视锥细胞反应、降低的视杆细胞反应，以及明视视锥细胞反应中具有特征性的ESCS波形，但在暗视闪光反应中未出现。序列分析显示NR2E3基因存在杂合突变，c.767C→T导致p.Ala256Val替换，以及外显子2之前剪接位点的突变，c.119-2A→C。
p.Ala256Val突变仅影响NR2E3核受体的配体结合域，导致ESCS的ERG结果出现轻度受损。
