CDC73 is a tumor suppressor gene that encodes a nuclear protein, named parafibromin, a component of the human PAF1 complex, which controls gene transcription by interacting with the subunit A of the RNA polymerase II, with the SUV39H1 histone methyltransferase complex (promoting H3K4 and H3K79 methylations), and with the RNF20/RNF40 ubiquitine ligase complex (promoting monoubiquitination of histone H2B at the lysine residue K120; H2BK120ub1). This evidence concerns the gene CDC73 and neoplasm.