Is Alagille syndrome always inherited?
No. In about half of the Alagille syndrome cases, the child inherits the gene mutation from a parent. The other half are what we call “new mutations,” meaning the mutation occurred in the gene, either when an egg or sperm cell was being made or in one of the first cells of the developing embryo. While parents whose children are diagnosed with Alagille syndrome often recall things that happened during the pregnancy, such as falls or exposures to chemicals or medications, it’s important to remember that nothing you do can cause or prevent these new mutations from occurring; they happen as a part of the natural cell division process. A person who has Alagille syndrome as a result of a new mutation has a 50 percent chance of passing that mutation on to his or her offspring. The child who does inherit a Jagged1 mutation will have some Alagille syndrome manifestations, but there is no way to predict how severely affected he or she will be. The severity of Alagille syndrome varies widely in c
