How common is Alagille syndrome?
It was first though that about 1 in 70,000 babies are born per year with Alagille syndrome. However, there might actually be more people with Alagille syndrome who have the condition, but are not diagnosed, if their symptoms are very mild. Alagille syndrome may occur in as many as 1 in 30,000 babies.
Alagille Syndrome. GeneReviews. https://www.ncbi.nlm.nih.gov/books/NBK1273/
Alagille Syndrome. Genetics Home Reference. https://ghr.nlm.nih.gov/condition/alagille-syndrome