T-cell-specific transcription factor 4 (TCF-4) participates in the Wnt signaling pathway and modulates MYC e, Xenopus/Amphibian,pression by binding to its promoter in a sequence-specific manner. TFC-4 acts as repressor in the absence of CTNNB1, and as activator in its presence. TCF-4 is necessary for the maintenance of the epithelial stem-cell compartment of the small intestine. Genetic variations in TCF-4 are associated with susceptibility to non-insulin-dependent diabetes mellitus (NIDDM). NIDDM is characterized by an autosomal dominant mode of inheritance, onset during adulthood and insulin resistance.