CTNNB1 and hepatoblastoma: Among the driver mutations, CTNNB1 (encoding beta-catenin) alterations were detected in 54 of the 59 samples (92%); all alterations were associated with exon 3 (Supplementary Figs. 1a and 2) and were reported to induce beta-catenin stabilization and hepatoblastoma tumorigenesis6,14.