Car4, or Carbonic anhydrase IV, is a human gene encoded by CA4. It may also be known as: Carbonic anhydrase 4; Carbonate dehydratase IV; CA-IV; Carbonic anhydrase 4 ; CAIV; RP17. The encoded protein is an enzyme with an amino acid length of 312 and a mass of 35.0 kDa. Car4 is a member of the Alpha-carbonic anhydrase family. Homologs of this gene exist in other organisms, including: Frog, Chicken.