Expanding the Clinical Spectrum of Variants: A Case Report on Non-Syndromic Retinal Dystrophy with a Mild Phenotype.

: Biallelic pathogenic variants in the gene are typically associated with severe, early-onset inherited retinal dystrophies (IRDs) in both syndromic and non-syndromic forms. This study explores the phenotypic variability of non-syndromic IRDs associated with variants, focusing on two siblings with biallelic variants, one of whom exhibits a remarkably mild phenotype, thereby expanding the clinical spectrum. : Whole-exome sequencing (WES) and mRNA analysis were performed to identify and characterize variants in the siblings. Comprehensive ophthalmologic evaluations assessed retinal function and disease progression. : Two variants, a frameshift (c.955del, p.(Ser319LeufsTer16)) and a missense (c.5777G>C, p.(Arg1926Pro)), were identified in in both siblings. Despite sharing the same genetic variants, the sister exhibited significantly preserved retinal function, while the brother presented with a more severe, progressive retinal dystrophy. : This study broadens the phenotypic spectrum of non-syndromic -related IRDs, demonstrating variability in disease severity ranging from mild to severe. These findings highlight the importance of personalized monitoring and tailored management strategies based on individual clinical presentations of -related IRDs.