J Korean Ophthalmol Soc.  2025 Jan;66(1):36-44. 10.3341/jkos.2025.66.1.36.

Genetic Characteristics of 63 Patients with Non-syndromic Retinitis Pigmentosa at a Single Korean Institution

• Kim SR
• Kim JH
• Yoon WT
• Lew YJ

• KMID: 2563919
• DOI: http://doi.org/10.3341/jkos.2025.66.1.36

Abstract

Purpose
To investigate the genetic characteristics of patients with non-syndromic retinitis pigmentosa (RP) analyzed at a single institution.
Methods
We conducted a retrospective analysis of 63 patients clinically diagnosed with non-syndromic RP who underwent genetic testing. The clinical features of patients exhibiting the most common mutations, EYS and USH2A, were further assessed through routine ophthalmic examinations.
Results
Of the 63 patients, 22 (34.9%) exhibited significant mutations. Notably, EYS and USH2A mutations were each found in 5 patients (7.9%); RP1 mutations were found in 4 patients (6.3%). The average ages at diagnosis were 38.8 years for EYS mutations and 41.8 years for USH2A mutations. The average best-corrected visual acuities were logMAR 0.08 for EYS mutations and logMAR 0.51 for USH2A mutations. Both mutation types showed a decrease in the normal macular area in fundus photographs with increasing age. In USH2A mutations, optical coherence tomography revealed a more pronounced reduction in central macular thickness and central foveal ellipsoid length compared with EYS mutations. Visual field tests indicated a reduction within the central 10° in 40% of EYS mutations and 60% of USH2A mutations. Electroretinography showed non-detectable responses in 2 individuals with EYS mutations and 4 individuals with USH2A mutations (40% and 80%, respectively).
Conclusions
EYS and USH2A mutations represented 45% of the genetically identified cases; affected patients typically were diagnosed in their 40s. EYS mutations tended to preserve retinal function and central foveal structure better than USH2A mutations.

Keyword

EYS protein, Genetics, Retinitis pigmentosa, USH2A protein