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

J Dent Res. 2016 Dec;95(13):1457-1463. doi: 10.1177/0022034516663200. Epub 2016 Aug 24.


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.

Keywords: enamel; enamel biomineralization/formation; genetics; genomics; molecular genetics; tooth development.

Publication types

  • Case Reports

MeSH terms

  • Amelogenesis Imperfecta / genetics*
  • Autoantigens / genetics*
  • Codon, Nonsense
  • Consanguinity
  • Female
  • Genotype
  • Humans
  • Male
  • Morocco
  • Non-Fibrillar Collagens / genetics*
  • Pedigree
  • Phenotype


  • Autoantigens
  • Codon, Nonsense
  • Non-Fibrillar Collagens
  • collagen type XVII