Roles for LEF/TCF proteins has been studied in tissue-culture and animal models of intestinal stem cells and colorectal cancer, which suggested roles for TCF7L2 and TCF7 in normal colorectal tissue, where LEF1 and TCF7L1 are silent, but strong expression in colorectal tumor of LEF1 [9,18,19,20,21] and TCF7 [22,23]. The gene discussed is TCF7L1; the disease is colorectal cancer.