Early studies into the potential involvement of SWI/SNF and tumor suppression were spurred by observations that core BAF subunits were absent in immortalized cell lines [89], and subsequent research found that the BAF core subunit BAF47 (SNF5) was disabled in almost all cases of malignant rhabdoid tumors (MRTs) [90, 91], an aggressive childhood cancer. This evidence concerns the gene SMARCB1 and rhabdoid tumor.