histone methyltransferase activity histone H2A methyltransferase activity https://github.com/geneontology/go-ontology/issues/22588 pg 2022-11-01T09:07:02Z Catalysis of the reaction: S-adenosyl-L-methionine + a histone H2 = S-adenosyl-L-homocysteine + a methylated histone H2A. Histone methylation generally occurs on either an arginine or a lysine residue. histone H2A methylase activity GO:0140940 histone H2A methylation molecular_function