# Clinical Characteristics and Genetic Factors in Retinitis Pigmentosa: A Retrospective Analysis of a Turkish Patient Cohort

## TL;DR

This study examines the clinical and genetic features of 95 Turkish patients with retinitis pigmentosa, highlighting patterns of inheritance and vision loss.

## Contribution

The study provides insights into the autosomal recessive inheritance and high consanguinity rates in a Turkish RP cohort.

## Key findings

- Most patients had severe vision loss and autosomal recessive inheritance patterns.
- Consanguineous marriage history was present in over half of the cases.
- CERKL and USH2A were the most commonly identified genes in genetic testing.

## Abstract

Background: Retinitis Pigmentosa (RP) is a group of inherited retinal dystrophies with significant genetic heterogeneity. The prevalence and clinical characteristics may vary among different populations due to genetic and cultural factors. Objective: To analyze the clinical characteristics, demographic distribution, and genetic factors of RP patients in this cohort of 95 Turkish RP patients. Methods: This retrospective study analyzed data from 95 RP patients collected through structured questionnaires and clinical records. Data included age of symptom onset, family history, consanguineous marriage history, visual acuity, and genetic test results. Results: The mean patient age was 36.0 ± 12.6 years (range: 13–71 years). Mean symptom onset age was 14.8 ± 11.1 years (range: 0–52 years). Positive family history was present in 53.1% (43/81) of evaluable patients. Consanguineous marriage history was found in 52.4% (43/82) of cases. Among patients with visual acuity data (n = 21), 85.7% had severe vision loss (≤10%), 4.8% had moderate vision loss (11–30%), and 9.5% had mild vision loss (>30%). Genetic testing was performed in 54.3% of patients, with CERKL and USH2A being the most commonly identified genes. Conclusions: This cohort of 95 Turkish patients with RP shows predominant autosomal recessive inheritance patterns with high rates of consanguineous marriage and positive family history. The majority of patients present with severe vision loss, and symptoms of onset typically occur during childhood and adolescence. These findings highlight the importance of genetic counseling and early diagnosis strategies in populations with high consanguinity rates.