Recombinant proteins for H2A histone family member X are available from various sources. In humans, this protein has a Uniprot ID of P16104 and has an annotated function: 'Variant histone H2A which replaces conventional H2A in a subset of nucleosomes.' This protein is 143 amino acids in length and 15.2 kilodaltons in mass. It has been designated a subcellular localization as: nuclear. This protein is encoded by the gene H2AFX. Other names also exist, such as: histone H2AX, H2AX histone, histone H2A.x. This protein is conserved in other species, including: rat.