Amelogenesis Imperfecta: 1 Family,2 Phenotypes,and 2 Mutated Genes

Amelogenesis imperfecta (ai) is a clinically and genetically heterogeneous group of diseases characterized by enamel defects. the authors have identified a large consanguineous moroccan family segregating different clinical subtypes of hypoplastic and hypomineralized ai in different individuals within the family. using targeted next-generation sequencing,the authors identified a novel heterozygous nonsense mutation in col17a1 (c.1873c>t,p.r625∗) segregating with hypoplastic ai and a novel homozygous 8-bp deletion in c4orf26 (c.39-46del,p.cys14glyfs∗18) segregating with hypomineralized-hypoplastic ai in this family. this study highlights the phenotypic and genotypic heterogeneity of ai that can exist even within a single consanguineous family. furthermore,the identification of novel mutations in col17a1 and c4orf26 and their correlation with distinct ai phenotypes can contribute to a better understanding of the pathophysiology of ai and the contribution of these genes to amelogenesis. © international & american associations for dental research 2016.