Table 1. Number of retinitis pigmentosa genes and loci.

Mapped and identified genes	CA4, CRX, FSCN2, GUCA1B, IMPDH1, NR2E3, NRL, PRPF3, PRPF8, PRPF31, PRPH2, RHO, ROM1, RP1, RP9, SEMA4A, TOPORS, ABCA4, CERKL, CNGA1, CNGB1, CRB1, LRAT, MERTK, NR2E3, PDE6A, PDE6B, PRCD, PROM1, RGR, RLBP1, RPE65, SAG, TULP1, USH2A, RP2, RPGR	37
Mapped loci (not identified)	RP33, RP22, RP25, RP28, RP29, RP32, RP6, RP23, RP24, RP34	10
Total		47

Tremendous research in the field of RP allowed the identification of nearly 47 genes. However, mutations in 37 genes are known to cause adRP and 10 adRP genes have been mapped but not identified yet (RetNet).