In contrast, all medulloblastomas showed some evidence of methylation of the CpG regions assessed in S100A4 and S100A2. Whereas the normal cerebellum and the majority of primary medulloblastomas (34 out of 41) and medulloblastoma cell lines (6 out of 9) demonstrated complete methylation (>75%) of the S100A4 intronic CpG sites analysed, a subset of primary tumours (17%; 7 out of 41) and cell lines (33%; 3 out of 9) were undermethylated in comparison, displaying either partial methylation or no evidence of methylation at each site (Figures 2D and 3). Here, S100A2 is linked to medulloblastoma.