In addition, it would be valuable to compare these results to the sleep phenotype of cases with nonsyndromic RP, for example, nonsyndromic RP caused by pathogenic variants in the EYS gene (which is the second most frequent cause of nonsyndromic RP),49 or nonsyndromic RP resulting from pathogenic variants in the USH2A gene.30 Here, USH2A is linked to retinitis pigmentosa 1.