TRPM3 and medulloblastoma: CpG island at the TRPM3/MIR204 promoter locus seems to be not methylated in Group 3 / Group 4 medulloblastomas based on the data from the Illumina 450 K array and bisulfite sequence analysis done on Group 3 medulloblastoma cell lines for the CpG island in the TRPM3/MIR204 promoter region (Fig. 8a; Additional file 4: Figure S3).