In contrast to medulloblastoma, the vast majority of cell lines derived from various normal and transformed tissues exhibited minimal to no DNase hypersensitivity in the vicinity of the OTX2 gene (Fig. 1; refer to UCSC Genome Browser at http://genome.ucsc.edu for additional cell line data), in agreement with SAGE data indicating that OTX2 is expressed in a restricted subset of normal tissues and tumor types (e.g. medulloblastoma and retinoblastoma) [35]. Here, OTX2 is linked to retinoblastoma.