We ascertained three related RP type 11 patients with a PRPF31 c.1115_1125del11 heterozygous mutation with variable phenotypic expression and one patient with severe RP with a PRPF31 c.522_527+10del heterozygous mutation (Supplementary Data 1). This evidence concerns the gene PRPF31 and retinitis pigmentosa 1.