Notionally, all the diverse retinal changes of the heterozygous females with an X-linked RP frame-shift mutation in RPGR gene should be suspected to be due to a peculiar truncation of RPGR protein21, 23, 26, 28, 31, and each of these carriers represents a mosaic of photoreceptors expressing either the wild type or the mutant allele. The gene discussed is RPGR; the disease is retinitis pigmentosa 1.