A previous report by Zindy and collaborators (Zindy et al., 2007) showed that SHH medulloblastoma induced by enforced expression of N-Myc in mouse GNP cells sustained loss of Ptch1. To address whether human WTC10 MYCN tumors similarly showed loss of PTCH1, we analyzed WTC10 MYCN tumors, identifying a SNP in a coding exon of PTCH1 (rs357564, P1315L) (Table S4). Here, MYCN is linked to medulloblastoma.