 Additionally, in terms of amino acid sequence, the location of fourteen cysteine residues is conserved; however, researchers describe glypicans as having moderate similarity in amino acid sequence overall.Nevertheless, it is thought that the fourteen conserved cysteine residues play a vital role in determining three-dimensional shape, thus suggesting the existence of a highly similar three-dimensional structure.Overall, GPC3 and GPC5 have very similar primary structures with 43% sequence similarity.