It is possible that the risk of HCC is related to the severity of BSEP deficiency and, thereby, the severity of inflammatory damage; for instance, in a retrospective cohort study, only 3% of patients with less severe ABCB11 mutations developed HCC by 15 years of age compared with 34% of patients with more severe ABCB11 mutations (i.e., mutations leading to nonfunctional or absent BSEP protein) [64]. The gene discussed is ABCB11; the disease is hepatocellular carcinoma.