Anti-H2AC18 antibodies are used in the immunodetection of the protein H2A clustered histone 18. It is notably widely expressed in many tissue types. Synonyms for this target antigen include H2A.2, H2A/O, H2A/q, H2AC19, H2AFO, H2a-615, HIST2H2AA, and H2A. H2AC18 gene orthologs have been reported in the rat species.