The GIL blood group system was added to the list of systems already recognized by the International Society for Blood Transfusion in 2002. It was designated as system 29 after the antigen was located on the aquaglyceroporin 3 (AQP3) protein and the gene encoding the protein was identified in 2002. There is only one antigenin the system, GIL, and the antigen, as well as the system, was named after the antigen-negative proband identified in the United States who had made anti-GIL. It was later shown to be the same as an unidentified high-incidence antigen lacking from the red blood cells of a French woman. Coincidentally all the antibodies found have been produced as a result of pregnancy. While there has not been a direct link to a disease, the absence of the AQP3 protein may result in a worse than expected rate of survival of patients with bladder cancer as compared with patients with the same disease who express the protein. Future work may center on using GIL as a marker for AQP3 and involving it in targeted cancer therapies.