USH2A and retinitis pigmentosa 1: For ADRP, RHO was identified to be responsible for the phenotype in one case, whereas, in ARRP and sporadic RP, USH2A, CNGB1, and TULP1 were the most recurrently mutated genes. RPE65 mutations were found in two ARRP cases: in one more case, still unsolved, a single RPE65 heterozygous pathogenic variant was found. ROM1 compound heterozygosity was established in one RP proband, suggesting a mechanism of recessive inheritance for this gene associated with dominant and digenic forms.