TY - JOUR

T1 - Dentinogenesis imperfecta type II- genotype and phenotype analyses in three Danish families

AU - Taleb, Kawther

AU - Lauridsen, Eva

AU - Daugaard-Jensen, Jette

AU - Nieminen, Pekka

AU - Kreiborg, Sven

N1 - © 2018 The Authors. Molecular Genetics & Genomic Medicine published by Wiley Periodicals, Inc.

PY - 2018/5

Y1 - 2018/5

N2 - BACKGROUND: Dentinogenesis imperfecta (DI) is a rare debilitating hereditary disorder affecting dentin formation and causing loss of the overlying enamel. Clinically, DI sufferers have a discolored and weakened dentition with an increased risk of fracture. The aims of this study were to assess genotype-phenotype findings in three families with DI-II with special reference to mutations in the DSPP gene and clinical, histological, and imaging manifestations.METHODS: Nine patients participated in the study (two from family A, four from family B, and three from family C). Buccal swab samples were collected from all participants and extracted for genomic DNA. Clinical and radiographic examinations had been performed longitudinally, and the dental status was documented using photographic images. Four extracted and decalcified tooth samples were prepared for histological analysis to assess dysplastic manifestations in the dentin. Optical coherence tomography (OCT) was applied to study the health of enamel tissue from in vivo images and the effect of the mutation on the function and structure of the DSPP gene was analyzed using bioinformatics software programs.RESULTS: The direct DNA sequence analysis revealed three distinct mutations, one of which was a novel finding. The mutations caused dominant phenotypes presumably by interference with signal peptide processing and protein secretion. The clinical and radiographic disturbances in the permanent dentition indicated interfamilial variability in DI-II manifestations, however, no significant intrafamilial variability was observed.CONCLUSION: The different mutations in the DSPP gene were accompanied by distinct phenotypes. Enamel defects suggested deficit in preameloblast function during the early stages of amelogenesis.

AB - BACKGROUND: Dentinogenesis imperfecta (DI) is a rare debilitating hereditary disorder affecting dentin formation and causing loss of the overlying enamel. Clinically, DI sufferers have a discolored and weakened dentition with an increased risk of fracture. The aims of this study were to assess genotype-phenotype findings in three families with DI-II with special reference to mutations in the DSPP gene and clinical, histological, and imaging manifestations.METHODS: Nine patients participated in the study (two from family A, four from family B, and three from family C). Buccal swab samples were collected from all participants and extracted for genomic DNA. Clinical and radiographic examinations had been performed longitudinally, and the dental status was documented using photographic images. Four extracted and decalcified tooth samples were prepared for histological analysis to assess dysplastic manifestations in the dentin. Optical coherence tomography (OCT) was applied to study the health of enamel tissue from in vivo images and the effect of the mutation on the function and structure of the DSPP gene was analyzed using bioinformatics software programs.RESULTS: The direct DNA sequence analysis revealed three distinct mutations, one of which was a novel finding. The mutations caused dominant phenotypes presumably by interference with signal peptide processing and protein secretion. The clinical and radiographic disturbances in the permanent dentition indicated interfamilial variability in DI-II manifestations, however, no significant intrafamilial variability was observed.CONCLUSION: The different mutations in the DSPP gene were accompanied by distinct phenotypes. Enamel defects suggested deficit in preameloblast function during the early stages of amelogenesis.

U2 - 10.1002/mgg3.375

DO - 10.1002/mgg3.375

M3 - Journal article

C2 - 29512331

VL - 6

SP - 339

EP - 349

JO - Molecular genetics & genomic medicine

JF - Molecular genetics & genomic medicine

SN - 2324-9269

IS - 3

ER -