E. Four alternative models for binding of normal and oncogenic FET proteins to SWI/SNF. (I): FET oncoproteins bind directly to SWI/SNF. (II): normal FET proteins form homo- and hetero-complexes and mediate binding of FET oncoproteins. (III): FET oncoproteins and normal FET proteins bind to different variants of the SWI/SNF complex with distinct biochemical compositions. (IV): FET oncoproteins and normal FET proteins bind to different sites on the SWI/SNF complex. 