Exome sequencing identifies novel genetic variants in patients with atypical Non-Syndromic retinitis pigmentosa

Retinitis Pigmentosa is the leading cause of hereditary blindness. This clinically and genetically heterogeneous group of disorders typically begins with night blindness and progresses to complete vision loss. In atypical cases, the classic triad of retinal bone-spicule pigmentation, blood vessel attenuation, and waxy disc pallor is absent, complicating definitive clinical diagnosis.

To identify the underlying genetic causes in diagnostically challenging cases, exome sequencing was conducted on eight unrelated patients with atypical, non-syndromic Retinitis Pigmentosa. Putative causative variants were confirmed, and segregation analysis was performed in available families using Sanger sequencing.

Exome sequencing detected three novel pathogenic variants: MAK:c.768delA, RP1:c.4743delA, and RPE65:c.95-2 A > G. Furthermore, several known variants previously associated with atypical RP phenotypes were identified in our study, reinforcing their role in the disease and underscoring the critical value of genetic testing for a conclusive diagnosis.

Our findings expand the mutational spectrum associated with Retinitis Pigmentosa, particularly in atypical cases. The identification of both novel and non-novel variants highlights the importance of Exome Sequencing in accurate diagnosis and possible personalized treatment.