DSPP Mutation In Dentinogenesis Imperfecta Shields Type Ⅱ And Mouse Model With Dspp Gene Mutation

Dentinogenesis imperfecta Shields type II (DGI-II, MIM 125490) is an autosomal dominant disorder in which both primary and permanent teeth are affected. It occurs with an incidence of 1:8000 live births. The teeth are amber and opalescent, with pulp chamber obliterated by abnormal dentin. The enamel, although unaffected, tends to fracture, which makes dentin undergo rapid attrition leading to a marked shortening of the teeth.The DGI-II locus was refined to 2 Mb interval on chromosome 4q21, in which a group of genes expressed in teeth that might be involved in dentin mineralization. Among these genes, dentin sialophosphoprotein (DSPP) is mainly expressed in odontoblasts and transiently in preameloblasts. Dentin sialoprotein and dentin phosphoprotein (DPP) are cleavage products expressed from a single transcript encoded by DSPP.We studied a Chinese family with dentinogenesis imperfecta Shields type II. All of the affected individuals showed discoloration and severe attrition of their teeth, with obliterated pulp chamber. Eight STRPs flanking the DGI-II locus were used to perform genetic linkage analysis in 13 individuals from this family. The 2-point linkage analysis with MLINK software support this locus located in chromosome 4q21.By direct sequencing PCR products which cover exons 1 -4 of DSPP and their flanking...