Diagnosis and Testing
Who else in my family should I test for Alagille syndrome?
First-degree relatives (parents, siblings, and children) should be tested for Alagille syndrome since the condition can cause very different symptoms in different people, and may not have been picked up in others until your diagnosis. If you have had genetic testing that found a JAG1 or NOTCH2 mutation, your relatives can be tested for that same mutation. If no mutation was found, other family members cannot be genetically tested. However, these relatives can be seen by doctors to look at their liver, heart, eyes, skeleton, and facial features to help determine if they have Alagille syndrome or not.