X-linked juvenile retinoschisis: phenotypic and genetic characterization

Juvenile X-linked retinoschisis(XLRS, MIM#312700) belongs to a group of the vitreoretinal dystrophies. We aimed to describe the phenotype-genotype correlation of three XLRS cases in juveniles with different novel mutations from the Lithuanian population. The patients demonstrated macular retinoschisis and typical cyst-like cavities on spectral-domain optical coherence tomography(SD-OCT) images. The mean central foveal thickness was 569.7 μm. Two patients presented with peripheral retinoschisis. Flash electroretinogram demonstrated a reduced b/a ratio(<1.0) in all patients. RS1(NM00330.3) gene coding exons Sanger sequencing was performed. RS1 c.599 G>T(p.R200 L) mutation was detected in one case, showing to be pathogenic in silico analysis. c.(927) ins C(p.W33 fs) mutation was identified for another patient, indicating the variant is possibly damaging in silico analysis. The third case was identified with a pathogenic mutation c.422 C>G(p.R141 H), HGMD CM981753. These are the first cases of XLRS in the Lithuanian population confirmed by molecular genotyping. Presented patients had a different genotype but similar phenotypic traits.