RTL1 and neuroblastoma: Generally, imprinted genes73 including IGF2, DLK1, RTL1, and L3MBTL1 (Figure 5A) were enriched among the genes with strongest (p = 3.6 × 10−6) and most frequent ASE (p = 0.0059, both Wilcoxon rank-sum test) (Figure 5B), showing that expression imbalance recapitulates imprinting in neuroblastoma.