hGH is produced as a single-chain, 191-amino acid 22-kDa protein (Lewis et al., 1980b). Alternate splicing of the second codon resulting in deletion of amino acids 31–46 yields a 20-kDa form (about 5–10% of pituitary hGH) (Lewis et al., 1980a). A small amount of 17-kDa hGH is formed as well (Cooke et al., 1988).
