From HCC cohorts from different countries, the most prevalent are activating mutations in CTNNB1 (which encodes β-catenin), followed by loss-of-function mutations in AXIN1, AXIN2, and APC. The relative mutation frequencies of these various Wnt/β-catenin signaling elements are different in HCC as compared with other cancers (e.g., sporadic colorectal cancer). The gene discussed is AXIN1; the disease is hepatocellular carcinoma.