encodes a high mobility group (HMG) box-containing transcription factor that plays a key role in the Wnt signaling pathway. The protein has been implicated in blood glucose homeostasis. Genetic variants of this gene are associated with increased risk of type 2 diabetes.TCF7L1 and TCF7L2 were not expressed in cells of the lymphoid lineage. The deduced amino acid sequences of the HMG boxes of TCF7L1, TCF7L2, and TCF7 show striking homology. That gene activation by the beta-catenin/TCF4 complex is a critical event in cancer development is indicated by the fact that a subset of colorectal cancers that lack somatic mutations in APC show somatic mutations in the beta-catenin gene. These mutations are presumed to render beta-catenin insensitive to regulation by APC and GSK3B.