Atypical mild enhanced S-cone syndrome with novel compound heterozygosity of the NR2E3 gene.
OBJECTIVE
To report mild enhanced s-cone syndrome (ESCS) associated with a novel heterozygous mutation of the NR2E3 gene.


METHODS
Observational case report.


METHODS
Clinical examination, optical coherence tomography (OCT), electroretinography (ERG), genetic analysis, and protein homology modeling.


RESULTS
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.


CONCLUSIONS
The p.Ala256Val mutation affects the ligand binding domain of the NR2E3 nuclear receptor only, resulting in modestly impaired ESCS ERG results.
Lam
Byron L
BL
Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida 33136, USA. blam@med.miami.edu
Goldberg
Jeffrey L
JL
Hartley
Kristen L
KL
Stone
Edwin M
EM
Liu
Mu
M
D002648:Child; D020256:Choroidal Neovascularization / Q000235:genetics; D004596:Electroretinography; D005260:Female; D006579:Heterozygote; D006801:Humans; D008958:Models, Molecular; D009154:Mutation; D057093:Orphan Nuclear Receptors; D010775:Photic Stimulation; D016133:Polymerase Chain Reaction; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics*; D017949:Retinal Cone Photoreceptor Cells / Q000503:physiopathology*; D012162:Retinal Degeneration / Q000235:genetics* / Q000503:physiopathology; D017299:Rod Opsins / Q000235:genetics*; D013577:Syndrome; D041623:Tomography, Optical Coherence; D014157:Transcription Factors / Q000235:genetics*; D014792:Visual Acuity
C403073:NR2E3 protein, human; D057093:Orphan Nuclear Receptors; D018160:Receptors, Cytoplasmic and Nuclear; D017299:Rod Opsins; D014157:Transcription Factors; C095853:short-wavelength opsin