However, initially we were puzzled by the fact that both infant SHH tumors and early embryonic CGNPs were characterized by low primary cilium expression, as the latter is believed to be indispensable for SHH signaling (Huangfu et al., 2003; Sasai and Briscoe, 2012; Wheway et al., 2018); how can we reconcile early embryonic CGNPs being the cell-of-origin for infant medulloblastoma exhibiting deregulated SHH signaling, if these cells are not capable of SHH signaling? The gene discussed is SHH; the disease is medulloblastoma.