Alagille syndrome was first identified in 1969 by Dr. Daniel Alagille, a French pathologist, who noted a combination of liver abnormalities, heart defects, and distinctive facial features in children (Fig. 1) (Alagille et al. 1969). This was followed by further contributions from Watson and Miller in 1973 (Watson and Miller 1973). In 1975, Alagille et al. officially established the diagnostic criteria for the condition (Alagille et al. 1975). Alagille syndrome (ALGS) is a rare genetic syndrome characterized by a range of features, including chronic cholestasis caused by a reduced number of bile ducts within the liver (paucity of intrahepatic bile ducts), stenosis of peripheral pulmonary artery, spinal segmental defects, distinct facial features, eye abnormalities such as posterior embryotoxon or anterior segment anomalies, pigmentary retinopathy, and kidneys dysplasia (Orphanet 2009). The prevalence is estimated at 1 in 70.000, based on cases involving neonatal liver disease. However, this is likely an underestimation, as it does not consider the condition’s variability and reduced penetrance, which were clarified through family studies and genetic testing (Turnpenny and Ellard 2012). Symptoms can present at any age of life (GARD 2025).