Other genetically modified mouse strains are also available, such as the Mdr2-/- (Abcb4-/-) mice that have been used as a model of sclerosing cholangitis (Fickert and Wagner, 2017[16]; Moncsek et al., 2018[46]) or genetic mouse models of Alagille syndrome (Adams et al., 2020[1]; Hankeova et al., 2021[27]; Niknejad et al., 2023[47]). The gene discussed is ABCB4; the disease is Alagille syndrome.