Monoallelic pathogenic variants of ATP8B1 have been reported to be a predisposing factor for phenotypes such as drug-induced cholestasis, intrahepatic cholestasis of pregnancy type 1, and transient neonatal cholestasis (11); therefore, it is suggested that there may be undiscovered pathogenic variants of ATP8B1 in patients with BRIC1. The gene discussed is ATP8B1; the disease is cholestasis.