CRD is caused by mutation in many genes such as ABCA4, ADAM9, C8orf37, CDHR1, CRX, DRAM2, GUCA1A, GUCY2D, PITPNM3, POC1B, PROM1, RAB28, RAX2, RIMS1, RPGRIP1, SEMA4A, and TTLL56. The gene discussed is POC1B; the disease is cone-rod dystrophy.