Anti-RUNX family transcription factor 1 antibodies are used for the immunodetection of the protein encoded by the RUNX1 gene. In humans, the canonical protein has a reported length of 453 amino acid residues and a mass of 48.7 kDa. Its subcellular localization is in the nucleus. Alternative splicing is reported to yield 11 different isoforms for this protein. It is reported to be expressed in all tissues examined except brain and heart. It is noted to be involved in the differentiation of certain cell types. Post-translational modifications have been described, including methylation and phosphorylation. Other names for this target antigen include AML1 and AML1-EVI-1. Gene orthologs have been identified in the mouse, rat, bovine, frog, zebrafish, chimpanzee and chicken species.