Transcription factor, which is involved in craniofacial development, in odontogenesis and in stomach organogenesis. May have a role in the differentiation of molars from incisors. Plays a role in suppressing endodermal Wnt activity. Binds to a regulatory module of the NCAM promoter. Expressed predominantly in the facial primordia, developing stomach, and proximal limbs. Expressed in areas of the first and second branchial arches, before any apparent cellular or morphologic differentiation. Later in development, all expressing tissue in this region, including the mesenchyme underlying the olfactory epithelium, the primary and secondary palate, the molar tooth papillae, and the stroma of the submandibular gland, appear to be derived from ectomesenchyme of neural crest origin. By day 16.5, all areas except the developing molars are BARX1-negative. In addition, BARX1 marks the area of the future stomach in the primitive gut at embryonic day 9.5, and is present in the mesenchymal wall of the stomach until embryonic day 16.5. Belongs to the BAR homeobox family.