SMARCB1 and familial rhabdoid tumor: Atypical Teratoid Rhabdoid Tumor /Rhabdoid Tumor predisposition syndrome (RTPS) is a disorder characterized by an increased risk to develop malignant rhabdoid tumours (MRT) generally due to constitutional loss or inactivation of one allele of deletion INI1/hSNF5/SMARCB1 gene located on chromosome 22q11.2.