A small percentage of AT/RT cases occur due to the loss of SMARCA4, another core member of the SWI/SNF chromatin remodeling family; moreover, single inherited mutations of either SMARCB1 or SMARCA4 contribute to rhabdoid tumor predisposition syndrome (RTPS) 1 or 2, respectively [39]. Here, SMARCB1 is linked to familial rhabdoid tumor.