Anti-cobalamin binding intrinsic factor antibodies are used for the immunodetection of the protein encoded by the CBLIF gene. In humans, the canonical protein has a reported length of 417 amino acid residues and a mass of 45.4 kDa. It is known to be a secreted protein. Alternative splicing is reported to yield 2 different isoforms for this protein. A member of the Eukaryotic cobalamin transport proteins protein family, it is reported to promote absorption of the essential vitamin cobalamin (Cbl) in the ileum. Post-translational modifications have been described, including glycosylation. The gene encoding this protein is implicated in Hereditary intrinsic factor deficiency. Other names for this target antigen include IF, IFMH, INF, TCN3, gastric intrinsic factor (vitamin B synthesis), intrinsic factor, and GIF. Gene orthologs have been identified in the mouse, rat, bovine, frog, chimpanzee and chicken species.