For epigenetic studies, we chose the distal region 1C of the PTCH1 promoter [29], and found only 1/6 of the medulloblastoma cell lines bearing methylation at the promoter, although two other cell lines also showed low expression levels of PTCH1. Among the medulloblastoma samples, 2/8 (25%) showed methylation together with lack of PTCH1expression. Here, PTCH1 is linked to medulloblastoma.