# Retinal Dystrophies Associated with Mutations in the RP1 Gene: Genotype–Phenotype Correlations

## TL;DR

This study examines 10 Italian patients with retinitis pigmentosa linked to RP1 gene mutations, exploring how genetic changes relate to clinical symptoms and disease progression.

## Contribution

The study provides new genotype–phenotype correlations for RP1-associated retinitis pigmentosa in an Italian cohort.

## Key findings

- Patients presented with hemeralopia and visual field constriction as main symptoms.
- Fundus autofluorescence and OCT confirmed typical retinitis pigmentosa features in most cases.
- The study highlights the potential for tailored therapies based on genetic variations in RP1.

## Abstract

Background: We evaluated the genetic and phenotypic features of a cohort of 10 Italian patients affected by Retinitis Pigmentosa (RP) associated with RP1 sequence variants. Methods: A retrospective, cross-sectional genotype–phenotype correlation study was conducted on a cohort of ten Italian patients (four males and six females) seen at Careggi University Hospital between 2012 and 2024, all affected by RP carrying pathogenic variants in the RP1 gene. A comprehensive ophthalmic assessment and pedigree analysis were performed, focusing on the onset of disease symptoms, the patient’s age at first diagnosis, follow-up duration, and the presence of comorbidities. Results: Our cohort included ten Italian patients with a mean age of 59 (range of 32–79 years). The median age when symptoms first presented was 43 years (range of 2–74), with a mean follow-up period of 9.3 ± 2.6 years. The main symptoms at presentation were hemeralopia and visual field constriction. Fundus examination revealed a classic RP phenotype. Fundus autofluorescence (FAF), optical coherence tomography (OCT), Electroretinogram (ERG), and visual field testing confirmed the typical features of classic retinitis pigmentosa in most cases. Conclusions: This single-center cohort of Italian patients provides insights into the clinical and genetic characteristics of RP1-associated RP. By comprehensively identifying genetic variations and their associated clinical manifestations, therapeutic interventions targeting specific genetic abnormalities can be better tailored. This approach holds promise for improving the prognosis and quality of life for individuals with RP1-associated RP.