Transcriptional repressor that acts as a negative regulator of chondrocyte maturation. PLays a role in distal stomach development; required for proper antral-pyloric morphogenesis and development of antral-type epithelium. In concert with GSC, defines the structural components of the middle ear; required for tympanic ring and gonium development and in the regulation of the width of the malleus (By similarity). Expressed at highest levels in cartilage, bone (osteosarcoma) and gut (small intestine and colon), whereas moderate expression is seen in trachea and brain. Expressed in visceral mesoderm and embryonic skeleton. The disease is caused by variants affecting the gene represented in this entry. Belongs to the NK-3 homeobox family.