NOTCH2 and Alagille syndrome: These individuals have all met the standards for clinical classification of ALGS, but do not have a pathogenic variant in JAG1 or NOTCH2. We hypothesize that these include patients with JAG1 variants not previously identified by conventional testing (Sanger sequencing and MLPA), as well as a subset of patients that will be found to have a different diagnosis with overlapping features of Alagille syndrome.