The Src family kinase Hck has a known function in hematopoiesis.36, 37 Interestingly, Hck was identified in a genome-wide study of potential Gli1 binding genes in CGNPs and in Shh-type medulloblastoma.38 As Shh/Gli target genes such as Gli1, Ptch1, Hhip and aPKC-ι/λ are Shh pathway regulators, it is possible that Hck also regulates Shh signaling. Here, PTCH1 is linked to medulloblastoma.