HTX5, or Nodal growth differentiation factor, is a human gene encoded by NODAL. It may also be known as: Nodal homolog. The encoded protein has an amino acid length of 347 and a mass of 39.6 kDa. Other isoforms may exist. HTX5 is a member of the TGF-beta family. Homologs of this gene exist in other organisms, including: Mouse, Rat, Frog, Chicken.