Anti-H4C9 antibodies are used in the immunodetection of the protein H4 clustered histone 9. It is notably widely expressed in many tissue types. Synonyms for this target antigen include H4/m, H4C1, H4C11, H4C12, H4C13, H4C14, H4C15, and H4-16. H4C9 gene orthologs have been reported in the rat and chimpanzee species.