The genes involved in vivo and in vitro studies in the risk of development of hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA) are ABCB11, ABCB4, TJP2, FXR, MYO5B, SLC51B, SLC25A13, NOTCH2, JAG1, TGR5 and HNF1B both in paediatric and non-paediatric populations [9]. The gene discussed is JAG1; the disease is hepatocellular carcinoma.