AMBN and dental enamel hypoplasia: This prediction confirmed the conclusions previously reached by many authors because (i) AMBN was located on chromosome 4 in a region containing the locus for AIH2, the autosomal hypoplastic form of AI [12, 47], and (ii) the important function of AMBN during amelogenesis, as illustrated by AMBN−/− mice that exhibit severe enamel hypoplasia [49].