SPON1 encodes the human gene, Spondin 1, extracellular matrix protein. It may also be known as: Spondin-1; Vascular smooth muscle cell growth-promoting factor; F-spondin; VSGP/F-spondin. The encoded protein has an amino acid length of 807 and a mass of 91.0 kDa. Other isoforms may exist. Homologs of this gene exist in other organisms, including: Mouse, Rat, Frog, Chicken.