Increased expression of genes encoding Notch ligand JAG1 and its receptor NOTCH2 was observed in BA livers compared with control by quantitative polymerase chain reaction analyses.
We analysed 30 subjects with Alagille syndrome, nine with incomplete Alagille syndrome and 17 with biliary atresia and detected pathogenic mutations in JAG1 or NOTCH2 in 24/30 subjects with Alagille syndrome and in 4/9 subjects with incomplete Alagille syndrome.