The non-collagenous dentin matrix proteins are involved in dentinogenesis imperfecta type II (DGI-II).
Dentinogenesis Imperfecta type II (DGI-II) is a localized form of mesodermal dysplasia of the dentin affecting both the primary and permanent dentitions. This is an autosomal-dominant disease in which there is a disorder in dentin mineralization. Several studies have localized DGI-II to human chromosome 4 in the region 4q 12-21. Many ECM genes-such as OPN, DMP1, DMP2, DMP3 (DSPP), and BSP-have been mapped to the same locus. Biochemical studies indicated that dentin phosphophoryn (DMP2) might be a candidate gene in DGI-II. In this study, we have used histological and RFLP analyses of tissues from a DGI-II-affected patient, as compared with two normal controls, to determine if DMP1, 2, or 3 was linked to DGI-II. The histology of the affected tooth was very different in the DGI-II patient as compared with the normals. In particular, the dentinal tubules in the DGI-II patient were very irregular, which could be the result of perturbations in the process of dentin formation. Patient and control DNA samples were digested with EcoRI or PstI and Southern-hybridized with the DMP1, DMP2, and DMP3 cDNAs. Few differences in the restriction pattern were observed between affected and normal samples for DMP1 and DMP3-3' region (phosphophoryn-like sequences) probes. On the other hand, DMP2 showed a dramatic shift in the restriction pattern in DGI-II. This study suggests that the different restriction enzyme digestion profiles of the DNA from the DGI-II patient, as probed by DMP2, might be related to the defective mineralization of dentin in DGI-II.
Thotakura
S R
SR
Department of Oral Biology, School of Dentistry, University of Illinois at Chicago, 60612, USA.
Mah
T
T
Srinivasan
R
R
Takagi
Y
Y
Veis
A
A
George
A
A
D002894:Chromosomes, Human, Pair 4; D003811:Dentinogenesis Imperfecta / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D016326:Extracellular Matrix Proteins / Q000235:genetics* / Q000378:metabolism*; D005260:Female; D005799:Genes, Dominant; D006801:Humans; D008297:Male; D009693:Nucleic Acid Hybridization / Q000379:methods; D010375:Pedigree; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D012150:Polymorphism, Restriction Fragment Length; D017422:Sequence Analysis, DNA; D012795:Sialoglycoproteins / Q000235:genetics / Q000378:metabolism; D014074:Tooth Calcification; D000099311:Dentin Sialophosphoprotein
D016326:Extracellular Matrix Proteins; D010750:Phosphoproteins; D012795:Sialoglycoproteins; D000099311:Dentin Sialophosphoprotein; C017630:phosphophoryn