The function of Ensembl gene identifier ENSG00000120733 (KDM3B, lysine demethylase 3B) is as follows. Histone demethylase that specifically demethylates 'Lys-9' of histone H3, thereby playing a central role in histone code. Demethylation of Lys residue generates formaldehyde and succinate. May have tumor suppressor activity. .