Mutations in CTNNB1 (β-catenin) are identified in 16%–54% of endometrioid ovarian cancer patients, and other mutations in APC, AXIN1, and AXIN2, which are key downstream proteins of the Wnt/β-catenin pathway, are also found in different types of ovarian cancer (32, 79). The gene discussed is CTNNB1; the disease is ovarian cancer.