A de novo splice-site variant in the retinitis pigmentosa 2 (RP2) gene identified in a symptomatic carrier woman.

This report presents the clinical and genetic findings of a patient with a de novo splice-site variant in the retinitis pigmentosa 2 (RP2) gene.A 32-year-old Japanese woman was experiencing night blindness and reduced visual acuity since her twenties. Her parents were not consanguineous, and she had no family history of ocular disease. Fundus examination revealed irregular-shaped degeneration and fundus autofluorescence imaging showed abnormal hypofluorescence in the area of the retinal degeneration. As whole exome sequencing on her and her parents revealed unremarkable in RetNetTM genes, she was diagnosed as a sporadic case of retinitis pigmentosa (RP). However, subsequent whole genome sequencing revealed a heterozygous variant (c.102 + 2_102 + 5del) in the RP2 gene, but her parents did not carry the variant. Based on these clinical and genetic findings, we concluded that the patient was a symptomatic female carrier of RP2-associated RP.This report underscores the importance of comprehensive genomic analysis and family-based evaluation in uncovering hidden inheritance patterns, specifically in symptomatic female carriers of X-linked retinal dystrophies that initially appear sporadic. This study represents the first report to characterize the clinical phenotype associated with the splice-site variant c.102 + 2_102 + 5del in RP2.