Osteogenesis imperfecta: clinical, biochemical and molecular findings

Clin Genet. 2006 Aug;70(2):131-9. doi: 10.1111/j.1399-0004.2006.00646.x.


Mutations in COL1A1 and COL1A2 genes, encoding the alpha1 and alpha2 chain of type I collagen, respectively, are responsible for the vast majority of cases of osteogenesis imperfecta (OI) (95% of patients with a definite clinical diagnosis). We have investigated 22 OI patients, representing a heterogeneous phenotypic range, at the biochemical and molecular level. A causal mutation in either type I collagen gene was identified in 20 of them: no recurrent mutation was found in unrelated subjects; 15 out of 20 mutations had not been reported previously. In two patients, we could not find any causative mutation in either type I collagen gene, after extensive genomic DNA sequencing. Failure of COL1A1/COL1A2 mutation screening may be due, in a few cases, to further clinical heterogeneity, i.e. additional non-collagenous disease loci are presumably involved in OI types beyond the traditional Sillence's classification.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Child
  • Child, Preschool
  • Collagen / analysis
  • Collagen / genetics*
  • Collagen Type I / genetics*
  • Collagen Type I, alpha 1 Chain
  • DNA Mutational Analysis
  • Female
  • Humans
  • Infant
  • Male
  • Mutation
  • Osteogenesis Imperfecta / diagnosis
  • Osteogenesis Imperfecta / genetics*
  • Osteogenesis Imperfecta / physiopathology
  • Pregnancy


  • Collagen Type I
  • Collagen Type I, alpha 1 Chain
  • Collagen

Associated data

  • OMIM/120150
  • OMIM/120160