Retinitis pigmentosa arising from EYS gene mutations have reported novel insights from combined measurements for a RP stage score system (RP-SSS)

Researchers at the Ophthalmology Unit, Fondazione Policlinico Universitario Agostino in Rome, has reported that pathogenic variants in the eyes shut homolog (EYS) gene are estimated ~ 5% of patients with autosomal recessive retinitis pigmentosa (arRP) and a recent study indicated that an analysis of pathogenic variants may correlate patients with disease severity.  Assessing disease severity and a relative early age was correlated with the central area of the RPE/photoreceptor atrophy.  In measuring specific testing, researchers commented that certain “correlations may be relevant in view of therapeutic interventions aimed at rescuing rods and cones in EYS-retinopathy”.

The research study was investigating the eyes shut homolog (EYS) gene, a gene and protein are not yet fully characterised although the protein product is understood to stabilize ciliary axonemes in rods and cones in humans supporting the maintenance of photoreceptor cells.  For a practical clinical context, recent researchers used a basic classification for disease severity in RP patients based on a scoring of best corrected visual acuity (BCVA), Goldmann visual field diameter and the ellipsoid zone (EZ) width. The RP stage score system (RP-SSS) appeared to be a valuable test and the assessment of measuring central macular atrophy (CRA) and automated sub-RPE illumination (SRI) measurement can correlate these measures to pathogenic variants in the EYS gene.

The clinical study enrolled 17 patients affected by RP due to variants in the EYS gene.  The results of the study showed a correlation between the stage of RP and the age and disease duration of patients. The researchers stated that the “such correlation revealed a severe stage at a relatively early age of 45, supporting the severity of the molecular pathology underlying this sub-type of RP”.  In addition, the increase in CRA area was positively correlated with a greater RP-SSS value, indicating an increase in the disease severity. Furthermore, it was correlated inversely with the EZ width and positively with LogMAR acuity.  In concluding their analysis the researchers proposed that the study “has provided new information concerning patients affected by Retinitis Pigmentosa associated with EYS gene mutations. In particular, in EYS-related RP the severity score was positively correlated with the central retinal atrophy, the central visual acuity and the EZ extension and increases with age and disease duration”. In brief, “these correlations may be relevant in view of therapeutic interventions aimed at rescuing rods and cones in EYS-retinopathy”.