SPAG17 encodes the human gene, Sperm associated antigen 17. It may also be known as: Sperm-associated antigen 17; Projection protein PF6 homolog; CT143; PF6. The encoded protein has an amino acid length of 2223 and a mass of 251.7 kDa. Other isoforms may exist. Homologs of this gene exist in other organisms, including: Mouse, Rat, Frog, Chicken.