Retinoblastomas lacking MYCN amplifications strongly expressed this gene group (pMYCNnon-A-MYCNAWilcoxon rank sum test = 0.0002623), and expression was highest in cluster A, followed by cluster B (pAC = 0.00058, pBC = 0.00227, pAB = 0.37503; Wilcoxon rank-sum test; Fig. 6h). This evidence concerns the gene MYCN and retinoblastoma.