title: Tooth agenesis in osteogenesis imperfecta related to mutations in the collagen type I genes.
abstract: BACKGROUND
  Osteogenesis imperfecta (OI) is a heterogeneous group of disorders of connective tissue, mainly caused by mutations in the collagen type I genes (COL1A1 and COL1A2). Tooth agenesis is a common feature of OI. We investigated the association between tooth agenesis and collagen type I mutations in individuals with OI.
  
  
  METHODS
  In this cohort study, 128 unrelated individuals with OI were included. Panoramic radiographs were analyzed regarding dentinogenesis imperfecta (DGI) and congenitally missing teeth. The collagen I genes were sequenced in all individuals, and in 25, multiplex ligation-dependent probe amplification was performed.
  
  
  RESULTS
  Mutations in the COL1A1 and COL1A2 genes were found in 104 of 128 individuals. Tooth agenesis was diagnosed in 17% (hypodontia 11%, oligodontia 6%) and was more frequent in those with DGI (P = 0.016), and in those with OI type III, 47%, compared to those with OI types I, 12% (P = 0.003), and IV, 13% (P = 0.017). Seventy-five percent of the individuals with oligodontia (≥6 missing teeth) had qualitative mutations, but there was no association with OI type, gender, or presence of DGI.
  
  
  CONCLUSIONS
  The prevalence of tooth agenesis is high (17%) in individuals with OI, and OI caused by a qualitative collagen I mutation is associated with oligodontia.
authors: Division of Pediatric Dentistry, Department of Dental Medicine, Karolinska Institutet, Stockholm, Sweden.
authors: B
authors: B
authors: Malmgren
authors: Division of Pediatric Dentistry, Department of Dental Medicine, Karolinska Institutet, Stockholm, Sweden.
authors: K
authors: K
authors: Andersson
authors: Department of Medical Sciences, Uppsala University, Uppsala, Sweden.
authors: K
authors: K
authors: Lindahl
authors: Department of Medical Sciences, Uppsala University, Uppsala, Sweden.
authors: A
authors: A
authors: Kindmark
authors: Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden.|Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
authors: G
authors: G
authors: Grigelioniene
authors: Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
authors: V
authors: V
authors: Zachariadis
authors: Division of Pediatric Dentistry, Department of Dental Medicine, Karolinska Institutet, Stockholm, Sweden.
authors: G
authors: G
authors: Dahllöf
authors: Neuropediatric unit, Karolinska University Hospital, Stockholm, Sweden.|Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
authors: E
authors: E
authors: Åström
mesh_terms: D000848:Anodontia / Q000000981:diagnostic imaging / Q000235:genetics*; D002648:Child; D024042:Collagen Type I / Q000235:genetics*; D000090602:Collagen Type I, alpha 1 Chain; D005260:Female; D006801:Humans; D008297:Male; D060885:Multiplex Polymerase Chain Reaction; D009154:Mutation / Q000235:genetics; D010013:Osteogenesis Imperfecta / Q000000981:diagnostic imaging / Q000235:genetics*; D011862:Radiography, Panoramic
chemical_list: C000601279:COL1A2 protein, human; D024042:Collagen Type I; D000090602:Collagen Type I, alpha 1 Chain
keywords: dentinogenesis imperfecta; hypodontia; mutations; oligodontia; osteogenesis imperfecta; tooth agenesis