Cystogenesis associated with nephronophthisis (NPH), which is caused by mutations of genes encoding for nephrocystin proteins (NPHPs) is considered to be driven by over-activation of canonical Wnt signaling, and NPHP4 causally inhibits canonical Wnt signaling through enabling proteolytic degradation of β-catenin [51]. This evidence concerns the gene NPHP4 and normal pressure hydrocephalus.