Contributor: Gordon K. Klintworth
Alagille syndrome (cholestasis with peripheral pulmonary stenosis, Alagille-Watson syndrome, arteriohepatic dysplasia, syndromatic hepatic ductular hypoplasia, OMIM #118450) is an inherited autosomal dominant syndrome characterized neonatal jaundice due to intrahepatic cholestasis caused by ductular hypoplasia together with dysmorphic facies (prominent broad forehead, pointed mandible, bulbous tip of the nose) together with abnormalities in the eye (deep set eyes, posterior embryotoxon, chorioretinal atrophy with pigment clumping), cardiovascular system (pulmonary valvular stenosis, peripheral arterial stenosis), bone (butterfly vertebrae, decrease in interpediculate distance in lumbar spine), central nervous system (absent deep reflexes, poor performance at school), extremities (variable degrees of foreshortening of fingers, short ulnae, short scaphoid bones, short distal phalanges) and sometimes kidney (renal dysplasia, renal artery stenosis, hypertension). The differential diagnosis of familial intrahepatic cholestasis includes Zellweger syndrome, cholestasis-lymphedema syndrome, Byler disease, cholestasis with defective formation of cholic acid, alpha-1-antitrypsin deficiency). Cholestasis with peripheral pulmonary stenosis results from a mutation in the JAG1 gene.
 

20(20p12).