library_construction_protocol: Tumor samples were isolated from eyes that were enucleated in the course of retinoblastoma therapy. Samples were kept frozen at -80°C until use. Total RNA was extracted via the Monarch Total RNA Miniprep kit (NEB); Expression of mutant RB1 allele was verified by RT-PCR. Production of strand-specific mRNA libraries with TruSeq Stranded mRNA kit, Illumina; done by CeGaT, Tübingen, Germany