Posters

Intrafamilial phenotype variability in two male siblings with cross-linked juvenile retinoschisis: dorzolamide treatment effect in the natural history of the disease

Poster Details

First Author: P.Christodoulou GREECE

Co Author(s):    G. Tanteles   N. Nayia   I. Katsimpris   S. Maria           

Abstract Details

Purpose:

Purpose: To investigate how genotype is related to phenotype and document correlations of genotype-phenotype with the response of topical administration of dorzolamide in siblings affected with X-linked juvenile retinoschisis (XLRS). Clinical findings were supported with familial gentic analysis with bi-directional Sanger sequencing of RS1 pathogenic variant.

Setting:

National Health System Hospital: General Hospital Of Patras " Agios Andreas"

Methods:

A retrospective study was carried out of two male siblings with genetically confirmed XLRS, treated with topical installation of dorzolamide. Optical coherence tomography, fundus fluorescein angiography, ultrasound scan and electroretinogram were used in the evaluation. Central macular thickness (CMT) and best corrected visual acuity were recorded monthly for eighteen months. Genetic analysis of the family was conducted for mutations in the gene which encodes the protein retinoschisin, responsible for retinoschisis (RS1). The study was conducted by the ethical standards stated in the declaration of Helsinki and was approved by an institutional review board; written consent was obtained from the patients.

Results:

Results: Improvement both in BCVA and OCT images was observed in the patient with the mild form of the disease whereas, the visual acuity and the OCT images of the patient with the severe form of the disease did not show any improvement.

Conclusions:

Conclusions: Intrafamilial phenotypic variability between individuals sharing identical pathogenic variant was documented. Both our patients had a pathogenic variant in a hemizygous state at a genomic location in exon 6 of the RS1 gene;Frameshift mutation that is likely to cause protein truncation was identified which is suggested to result in greater clinical severity; contrary to our cases where both extremes of the severity spectrum were identified. Consequently, it was found that response to dorzolamide is correlated to phenotypic severity.

Financial Disclosure:

... gains financially from competing product or procedure, ... travel has been funded, fully or partially, by a company producing, developing or supplying the product or procedure presented, ... research is funded, fully or partially, by a company producing, developing or supplying the product or procedure presented, ... receives non-monetary benefits from a company producing, developing or supplying the product or procedure presented, ... receives consulting fees, retainer, or contract payments from a company producing, developing or supplying the product or procedure presented, ... is employed by a competing company, ... has significant investment interest in a company producing, developing or supplying product or procedure presented