Simultaneous ablation of Otx2 in the Otx2CreERT2/flox;R26SmoM2/SmoM2 sKO line neither affected early GCP expansion and EGL hyperplasia at P11 and P15 (Fig. 5a, b) nor the extent of tumoral development at P30 (Fig. 5c), or tumour size before this stage (sup. This evidence concerns the gene OTX2 and neoplasm.