Further analyses revealed higher levels of both global and locus-specific L1 RNA expression in tumor tissues compared to normal tissues across all three major groups (EU_N, AS_N, and EU_S; Fig. 5d; Supplementary Fig. 35), as well as significantly higher expression in tumors with ID2 compared to those without ID2 (P = 0.021; Fig. 5e). This evidence concerns the gene ID2 and neoplasm.