We previously reported the formation of medulloblastoma-like tissue in teratomas generated from NBCCS patient-derived induced pluripotent stem cells (iPSCs) and the loss of heterozygosity or a second mutation in the PTCH1 gene in the medulloblastoma, but not in the non-medulloblastoma portion of the teratoma [19]. This evidence concerns the gene PTCH1 and medulloblastoma.