Gpc3 expression correlates with the phenotype of the Simpson-Golabi-Behmelsyndrome

Interest in glypican-3 (GPC3), a member of the glypican-related integral me mbrane heparan sulfate proteoglycans (GRIPS) family, has increased with the finding that it is mutated in the Simpson-Golabi-Behmel overgrowth syndrom e (Pilia et al. [1996] Nat. Genet. 12:241-247). The working model suggested that the membrane-bound protein acts locally to limit tissue and organ gro wth and that it may function by interacting with insulin-like growth factor 2 (IGFS) to limit its local effective level. Here we have tested two predi ctions of the model. In situ hybridization with the mouse gene cDNA was use d to study the expression pattern during embryonic and fetal development. I n agreement with predictions, the gene is expressed in precisely the organs that overgrow in its absence; and the patterns of expression of Gpc3 and t hose reported for Igf2 are strictly correlated. Dev. Dyn. 1998;213:431-439. (C) 1998 Wiley-Liss, Inc.