CYGF, or Guanylate cyclase 2F, retinal, is a human gene encoded by GUCY2F. It may also be known as: Retinal guanylyl cyclase 2; RETGC-2; Guanylate cyclase F; GC-F; Rod outer segment membrane guanylate cyclase 2; ROS-GC2; guanylate cyclase 2D-like, membrane (retina-specific); GUC2DL; GUC2F. The encoded protein is an enzyme with an amino acid length of 1108 and a mass of 124.9 kDa. Other isoforms may exist. CYGF is a member of the Adenylyl cyclase class-4/guanylyl cyclase family. Homologs of this gene exist in other organisms, including: Mouse, Rat, Zebrafish, Frog, Chicken.