The BRG1 subunit of the SWI/SNF complex is mutated in human cancer and has been shown to be a tumor suppressor in mice (Love et al., 2012; Hodis et al., 2012; Parsons et al., 2011; Medina et al., 2008; Shain et al., 2012; Bultman et al., 2000, 2008; Glaros et al., 2008). Here, SMARCA1 is linked to neoplasm.