Whole-Exome sequencing identifies FAM20A mutations as a cause of amelogenesis imperfecta and gingival hyperplasia syndrome

Am J Hum Genet. 2011 May 13;88(5):616-20. doi: 10.1016/j.ajhg.2011.04.005. Epub 2011 May 5.


Amelogenesis imperfecta (AI) describes a clinically and genetically heterogeneous group of disorders of biomineralization resulting from failure of normal enamel formation. AI is found as an isolated entity or as part of a syndrome, and an autosomal-recessive syndrome associating AI and gingival hyperplasia was recently reported. Using whole-exome sequencing, we identified a homozygous nonsense mutation in exon 2 of FAM20A that was not present in the Single Nucleotide Polymorphism database (dbSNP), the 1000 Genomes database, or the Centre d'Etude du Polymorphisme Humain (CEPH) Diversity Panel. Expression analyses indicated that Fam20a is expressed in ameloblasts and gingivae, providing biological plausibility for mutations in FAM20A underlying the pathogenesis of this syndrome.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ameloblasts / metabolism
  • Amelogenesis Imperfecta / genetics*
  • Amelogenesis Imperfecta / pathology*
  • Chromosomes, Human, Pair 17
  • Dental Enamel Proteins / genetics*
  • Exons
  • Gene Expression Regulation
  • Genetic Heterogeneity
  • Gingival Hyperplasia / pathology*
  • Homozygote
  • Humans
  • Mutation*
  • Pedigree
  • Polymorphism, Single Nucleotide
  • Syndrome


  • Dental Enamel Proteins