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. This evidence concerns the gene RAX2 and cone-rod dystrophy.