Owing to the rapidly developing tumor genome sequencing technology, mutations in the genes encoding SWI/SNF subunits have been widely detected in multiple tumors, from inactivated biallelic mutations of SMARCB1(BAF47) being present in nearly all rhabdoid tumors to the discovery that ARID1A is mutated in nearly 50% of all ovarian clear cell carcinomas (OCCCs) and ovarian endometrioid carcinomas (OECs) [32,33], and the finding of approximately 40% of clear-cell renal cell carcinoma (ccRCC) cases possess PBRM1 mutations (Table 2) [34]. The gene discussed is SMARCB1; the disease is ovarian clear cell cancer.