Data from: Mutations in COL1A1 and COL1A2 and dental aberrations in children and adolescents with osteogenesis imperfecta - a retrospective cohort study

Osteogenesis imperfecta (OI) is a heterogeneous group of disorders of
connective tissue, caused mainly by mutations in the collagen I genes
(COL1A1 and COL1A2). Dentinogenesis imperfecta (DGI) and other dental
aberrations are common features of OI. We investigated the association
between collagen I mutations and DGI, taurodontism, and retention of
permanent second molars in a retrospective cohort of 152 unrelated
children and adolescents with OI. The clinical examination included
radiographic evaluations. Teeth from 81 individuals were available for
histopathological evaluation. COL1A1/2 mutations were found in 104
individuals by nucleotide sequencing. DGI was diagnosed clinically and
radiographically in 29% of the individuals (44/152) and through isolated
histological findings in another 19% (29/152). In the individuals with a
COL1A1 mutation, 70% (7/10) of those with a glycine substitution located
C-terminal of p.Gly305 exhibited DGI in both dentitions while no
individual (0/7) with a mutation N-terminal of this point exhibited DGI in
either dentition (p = 0.01). In the individuals with a COL1A2 mutation,
80% (8/10) of those with a glycine substitution located C terminal of
p.Gly211 exhibited DGI in both dentitions while no individual (0/5) with a
mutation N-terminal of this point (p = 0.007) exhibited DGI in either
dentition. DGI was restricted to the deciduous dentition in 20
individuals. Seventeen had missense mutations where glycine to serine was
the most prevalent substitution (53%). Taurodontism occurred in 18% and
retention of permanent second molars in 31% of the adolescents. Dental
aberrations are strongly associated with qualitatively changed collagen I.
The varying expressivity of DGI is related to the location of the collagen
I mutation. Genotype information may be helpful in identifying individuals
with OI who have an increased risk of dental aberrations.