GAPex5, or GTPase activating protein and VPS9 domains 1, is a human gene encoded by GAPVD1. It may also be known as: GTPase-activating protein and VPS9 domain-containing protein 1; GAPex-5; Rab5-activating protein 6; GAPEX5; RAP6. The encoded protein has an amino acid length of 1478 and a mass of 165.0 kDa. Other isoforms may exist. GAPex5 is a member of the GAPVD1 family. Homologs of this gene exist in other organisms, including: Mouse, Rat, Zebrafish, Frog, Chicken.