A comprehensive map of missense trafficking variants in rhodopsin and their response to pharmacologic correction

Abstract

Rhodopsin (RHO) missense variants are a leading cause of autosomal dominant retinitis pigmentosa (adRP), a progressive retinal degeneration. Interpreting RHO variant pathogenicity is challenging, and understanding their disease mechanisms is essential for developing therapeutics. We present a high-resolution map of RHO missense variant trafficking using deep mutational scanning approaches, including a surface abundance immunoassay and a complementary membrane proximity assay. This comprehensive, reproducible dataset encompassed all 6612 possible missense variants. Over 700 variants had pathogenic trafficking scores, substantially expanding the number of RHO variants with functional data. Trafficking scores correlated with the magnitude of ER stress markers and ClinVar pathogenicity classifications. Data also identified structurally clustered mutational intolerance around the intradiscal beta-plug region. Treatment with the chaperone YC-001 restored surface trafficking in most mistrafficking variants. This functional map of RHO variants provides a valuable resource for pathogenicity assessment, genotype-phenotype correlations, and the development of targeted therapeutic strategies for RHO-adRP.