Unusual Phenotypic Expression of an XLRS1 Mutation in X-Linked Juvenile Retinoschisis

Abstract

X-linked juvenile retinoschisis is a rare progressive vitreoretinal degenerative process that appears in early childhood, results in decreased visual acuity and blindness (if severe), and is caused by various mutations within the XLRS1 gene at Xp22.2. We report an affected family of Western European ancestry with X-linked juvenile retinoschisis. The family was found to carry a 304C-->T substitution in exon 4 of the XLRS1 gene, resulting in an Arg102Trp amino acid substitution. Two of the four available clinical cases in this family were found to carry the mutation. All available mothers of affected males were found to be unaffected carriers of the mutation, a typical feature of X-linked diseases. Two new female carriers, sisters of affected males, were identified and counseled accordingly. Questionnaires on visual functioning were given to the affected family members to examine the psychologic and sociologic impact of X-linked juvenile retinoschisis, which documented an associated stigma even when affected with a "mild" phenotype.

The gene mutation in a Taiwanese family with X‐linked retinoschisis

“…The proband (II‐2) was found to have a 304C→T base substitution in Exon 4 of the XLRS1 gene, a mutation previously identified in several other families worldwide [15,32,34–37]. According to the current literature, the logMAR BCVA of the XLRS patients with the same missense mutation ranges from 0.20 to 1.30.…”

Clinical and molecular characterization of females affected by X‐linked retinoschisis

“…In this study, we revealed the genetic diagnosis of affected males and females within a consanguineous XLRS family, and comparatively analysed their disease phenotypes. The detected RS1 variant c.304C > T has been previously reported in two Western European families, a cluster of families from the United Kingdom and various other populations including China . The encoded non‐synonymous change p.Arg102Trp is located within the phylogenetically conserved discoidin domain of the retinoschisin protein.…”

Retinosquise juvenil: relato de caso

“…A retinosquise juvenil, também chamada retinosquise hereditária congênita, é uma desordem vítreorretiniana relativamente rara, que origina baixa acuidade visual em homens jovens (1)(2)(3)(4)(5)(6) . É transmitida como herança ligada ao X e tem como principal causador o gene XLRS1 e suas mutações (2)(3)(7)(8) .…”

“…É transmitida como herança ligada ao X e tem como principal causador o gene XLRS1 e suas mutações (2)(3)(7)(8) . A baixa acuidade visual desenvolve-se na primeira década, é bilateral, em geral com rápida progressão até os dez anos de idade.…”

“…Mácula com estriações radiadas e aspecto cistóide é o achado principal da retinosquise em pacientes jovens além da retinosquise inferotemporal bilateral. No caso descrito neste artigo não foi encontrado degeneração retiniana perifé-rica tipo retinosquise em nenhum dos olhos, por outro lado a lesão macular bilateral encontrada foi característica (1,3,5,7,(9)(10)(11) . A retinografia fluorescente, neste caso descrito, teve sua contribuição no diagnóstico diferencial entre retinosquise e edema macular cistóide.…”