CRX and retinoblastoma: Comparison of DHS sites among cell lines revealed a prominent DHS (DHS “R”) in retinoblastoma located between DHS sites 3 and 4 (Figs. 1 and S1A) that is present at variable intensity in medulloblastoma cells (Fig. 6A) and whose ortholog is bound in the mouse eye by the retinal transcription factor Crx (Fig. S4) [40].