Any of a family of cell-signalling molecules that play key roles in tissue formation in both embryos and adult animals. Their role in the induction of bone formation was first discovered in the 1960s, and since then over 20 BMPs have been identified in various other tissues, instrumental in the development of heart muscle, nerves, and cartilage among others. Recombinant human BMP-2 is used therapeutically to promote bone growth in various interventions, e.g. to promote spinal fusion or to treat nonunion of a fracture. Most BMPs belong to the transforming growth factor-β‎ superfamily of proteins. See also morphogen.