AT-rich interactive domain 1A (ARID1A), a component of the BAF complex, has been identified by next-generation sequencing as one of the most frequently mutated genes in a variety of cancers, including ovarian clear cell carcinoma (OCCC)3, gastric cancer4, hepatocellular carcinoma5, esophageal adenocarcinoma6, breast cancer7, pancreatic cancer8 and colorectal cancer (CRC)9. The gene discussed is ARID1A; the disease is colorectal carcinoma.