In contrast, inhibition of Hh signaling using GLI and SMO small molecule antagonists Gant61 and Sant2 respectively prevented cyst formation in kidney explants from Ttc21b/Ift139-conditional knockout, jck/Nek8/Nphp9 and Pkd1 mutant mice (Tran et al., 2014). Here, TTC21B is linked to cyst.