Disruption of the CASK–Dlg1 interaction (through loss of the SH3 domain of Dlg1) (Naim et al., 2005) has been reported to impair normal kidney development and lead to the formation of cystic kidneys (Naim et al., 2005); given our results in vitro with dog kidney cells in 3D culture, we suspect that this may in part be due to the role of CASK in spindle orientation. The gene discussed is DLG1; the disease is Renal cyst.