PPIG and neoplasm: In the liver, CYP3A5 accounts for 20% of the CYP enzyme system in the liver, while the others are expressed in some organs, such as kidney, lung, prostate, intestinal wall, and some tumor tissues.[21] CYP3A5 enzyme is located in chromosome 7, with the gene full length of 31.8 kb; it contains 13 exons and encodes 502 amino acids.