T-box transcription factor 2 Tbx2 is a transcription factor that is encoded by the Tbx2 gene on chromosome 17q21-22 in humans. This gene is a member of a phylogenetically conserved family of genes that share a common DNA-binding domain, the T-box. Tbx2 and Tbx3 are the only T-box transcription factors that act as transcriptional repressors rather than transcriptional activators, and are closely related in terms of development and tumorigenesis. This gene plays a significant role in embryonic and fetal development through control of gene expression, and also has implications in various cancers. Tbx2 is associated with numerous signaling pathways, BMP, TGFβ, Wnt, and FGF, which allow for patterning and proliferation during organogenesis in fetal development. Role in development The molecule Tbx-2 is a transcription factor in the T box transcription factor family. Tbx2 helps form the outflow tract and atrioventricular canal. Tbx2 can repress genes as well as being competitors that take over binding sites. It also plays a role in cancer because it will suppress cell growth and supports invasiveness. In human melanoma, the expression of endogenous Tbx 2 is shown to help reduce the growth of melanomas. It has also been shown that overexpression of Tbx2 can lead to breast cancer. Tbx2 has shown septal defects of the outflow tract, and this has been shown using a knockout mouse. The knockout mouse is a mouse in which the gene is inactivated in order to study the role of genes. Tbx 2 also helps in regulating the cell cycle. This was first shown when Tbx2 was found in a chromosomal region that is often mutated in ovarian cancer and pancreatic cancer cells. During fetal development, the relationship of Tbx2 to FGF, BMP, and Wnt signaling pathways indicates its extensive control in development of various organ systems. It functions predominantly in the patterning of organ development rather than tissue proliferation. Tbx2 has implications in limb development, atrioventricular development of the heart, and development of the anterior brain tissues. During limb bud development, Shh and FGF signaling stimulate the outgrowth of the limb. At a certain point, Tbx2 concentrations are such that the signaling of Shh and FGF are terminated, halting further progression and outgrowth of the limb development. This occurs directly through Tbx2 repressing the expression of Grem1, creating a negative Grem1 zone, thereby disrupting the outgrowth signaling by Shh and FGF. Cardiac development is heavily regulated and requires the