Dental properties, ultrastructure, and pulp cells associated with a novel DSPP mutation

• Published in: Oral diseases Vol. 24; no. 4; pp. 619 - 627
• Main Authors: Porntaveetus, T, Osathanon, T, Nowwarote, N, Pavasant, P, Srichomthong, C, Suphapeetiporn, K, Shotelersuk, V
• Format: Journal Article
• Language: English
• Published: Denmark Wiley Subscription Services, Inc 01.05.2018; Wiley
• Subjects: Base Sequence; CD105 antigen; Cell Differentiation; Cell growth; Cell Proliferation; Cells, Cultured; Child, Preschool; Clonal deletion; Colonies; Colony-Forming Units Assay; Dental enamel; Dental Pulp; dental pulp cells; Dentin; dentin sialophosphoprotein; dentinal tubules; Dentinogenesis; Dentinogenesis Imperfecta; Dspp protein; Endoglin; exome sequencing; Extracellular Matrix Proteins; Gene deletion; Humans; Life Sciences; Male; Mesenchyme; Mutation; Pedigree; Phenotype; Phosphoproteins; Physical characteristics; Pluripotency; Sequence Deletion; Sialoglycoproteins; Stem cells; Teeth; Tubules; Ultrastructure; dentinogenesis imperfecta; dentin sialophosphoprotein; dental pulp cells; exome sequencing; dentinal tubules
• ISSN: 1354-523X; 1601-0825; 1601-0825
• DOI: 10.1111/odi.12801

Objective To investigate physical characteristics and behaviours of dental pulp cells of teeth isolated from a dentinogenesis imperfecta (DGI) patient with a novel dentin sialophosphoprotein (DSPP) mutation. Subjects and Methods Whole exome and Sanger sequencing were employed to identify mutations. Physical characteristics of the teeth were examined. Pulp cells’ behaviours including cell proliferation, colony‐forming unit, osteogenic differentiation, pluripotent markers, and mesenchymal stem cell markers were investigated. Results The proband had opalescent brown primary teeth with extensive loss of enamel. Mutation analysis revealed a novel heterozygous 4‐bp deletion, c.1915_1918delAAGT (p.K639QfsX674), in exon 5 of the DSPP associated with DGI. Analysis of the extracted primary incisor demonstrated a decrease in brightness but an increase in yellow and red chroma. The dentin showed reduced mineral density. The dentinal tubules were present in the predentin, but progressively collapsed in the dentin. The pulp cells exhibited markedly reduced CD105 expression, decreased cell proliferation, and smaller colony‐forming units. Conclusions We identified a novel mutation in the DSPP gene which disturbed dentin characteristics and pulp cells’ behaviours. Our study expands the mutation spectrum and understanding of pathologic dentin phenotypes related to the frameshift deletion in the dentin phosphoprotein (DPP) region of the DSPP gene.