TL;DR: In this paper, a series of OV-specific mutations in the heparan sulfate proteoglycans (HSPG) N-sulfotransferase genes (Ndst1 and Ndst2) were generated in mice.
TL;DR: These results suggest that HSPGs, depending on their HS sulfation pattern, regulate multiple signaling pathways in optic disc and stalk morphogenesis.