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

Abstract

Rhodopsin (<i>RHO</i>) missense variants are a leading cause of autosomal dominant retinitis pigmentosa (adRP), a progressive retinal degeneration. Interpreting <i>RHO</i> variant pathogenicity is challenging, and understanding their disease mechanisms is essential for developing therapeutics. We present a high-resolution map of <i>RHO</i> 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 <i>RHO</i> 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 <i>RHO</i> variants provides a valuable resource for pathogenicity assessment, genotype-phenotype correlations, and the development of targeted therapeutic strategies for <i>RHO</i>-adRP.