Interleukin 7 is a human gene encoded by the symbol, IL7. It may also be known as: Interleukin-7; IL-7. The encoded protein has an amino acid length of 177 and a mass of 20.2 kDa. Other isoforms may exist. Interleukin 7 is a member of the IL-7/IL-9 family. Homologs of this gene exist in other organisms, including: Mouse.