Cell surface heparan sulfate proteoglycans are composed of a membrane-associated protein core substituted with a variable number of heparan sulfate chains. Members of the glypican-related integral membrane proteoglycan family (GRIPS) contain a core protein anchored to the cytoplasmic membrane via a glycosyl phosphatidylinositol linkage. These proteins may play a role in the control of cell division and growth regulation. The GPC4 gene is adjacent to the 3' end of GPC3 and may also play a role in Simpson-Golabi-Behmel syndrome.
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Sheu TJ, Schwarz EM, O'Keefe RJ, Rosier RN, Puzas JE (May 2002). "Use of a phage display technique to identify potential osteoblast binding sites within osteoclast lacunae". Journal of Bone and Mineral Research. 17 (5): 915–22. doi:10.1359/jbmr.2002.17.5.915. PMID12009023.
Veugelers M, Cat BD, Muyldermans SY, Reekmans G, Delande N, Frints S, Legius E, Fryns JP, Schrander-Stumpel C, Weidle B, Magdalena N, David G (May 2000). "Mutational analysis of the GPC3/GPC4 glypican gene cluster on Xq26 in patients with Simpson-Golabi-Behmel syndrome: identification of loss-of-function mutations in the GPC3 gene". Human Molecular Genetics. 9 (9): 1321–8. doi:10.1093/hmg/9.9.1321. PMID10814714.