Anti-FTO alpha-ketoglutarate dependent dioxygenase antibodies are used for the immunodetection of the protein encoded by the FTO gene. In humans, the canonical protein has a reported length of 505 amino acid residues and a mass of 58.3 kDa. Its subcellular localization is in the nucleus, cytoplasmic vesicles, and cytoplasm. Alternative splicing is reported to yield 4 different isoforms for this protein. It is widely expressed across many tissue types. A member of the Fto protein family, it is reported to be a RNA demethylase that mediates oxidative demethylation of different RNA species, such as mRNAs, tRNAs and snRNAs, and acts as a regulator of fat mass, adipogenesis and energy homeostasis. Other names for this target antigen include AlkB homolog 9, U6 small nuclear RNA (2'-O-methyladenosine-N(6)-)-demethylase FTO, U6 small nuclear RNA N(6)-methyladenosine-demethylase FTO, and alpha-ketoglutarate-dependent dioxygenase FTO. Gene orthologs have been identified in the mouse, rat, bovine, frog, zebrafish, chimpanzee and chicken species.