title: Novel missense mutations in PAX9 causing oligodontia.
abstract: OBJECTIVE
  We investigated the disease-causing gene of oligodontia in Chinese families and analysed the pathogenesis of mutations of this gene that results in oligodontia.
  
  
  METHODS
  Two families with oligodontia, but of different descent and 100 unrelated healthy controls were enrolled in our study. Genomic DNA was isolated from blood samples. Mutation analysis was performed by amplifying MSX1 and PAX9 exons and sequencing the products. After identifying the mutations, we performed site-directed mutagenesis to generate mutated vectors. The wild-type and mutated PAX9 vectors were then transfected separately to NIH3T3 cells. Immunolocalization, electrophoretic mobility shift assay (EMSA) and luciferase reporter assay were performed to analyse the effects of mutations on protein function.
  
  
  RESULTS
  We identified two novel missense mutations, Leu27Pro (L27P) and Ile29Thr (I29T) in the paired-domain of PAX9. Analysis of homologous PAX proteins indicated that these two substitutions may affect the function of the PAX9 protein. Results of immunofluorescence and western blot showed that the mutations did not alter the nuclear localization of PAX9. EMSA and luciferase reporter assays indicated that both the mutated proteins could not bind DNA or transactivate the BMP4 promoter.
  
  
  CONCLUSIONS
  Two novel missense mutations in PAX9 have been indentified in Chinese families causing oligodontia.
authors.affiliation: The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, 237 Luoyu Road, Wuhan 430079, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Liang
authors.forename: Guangtai
authors.initials: G
authors.lastname: Song
authors.forename: Qing
authors.initials: Q
authors.lastname: Li
authors.forename: Zhuan
authors.initials: Z
authors.lastname: Bian
mesh_terms: D015153:Blotting, Western; D016022:Case-Control Studies; D002478:Cells, Cultured; D002681:China; D003062:Codon; D004252:DNA Mutational Analysis; D024202:Electrophoretic Mobility Shift Assay; D005260:Female; D006801:Humans; D008156:Luciferases; D008297:Male; D016297:Mutagenesis, Site-Directed; D020125:Mutation, Missense; D051764:PAX9 Transcription Factor / Q000235:genetics*; D010375:Pedigree; D010641:Phenotype; D014071:Tooth Abnormalities / Q000235:genetics*; D014162:Transfection
chemical_list: D003062:Codon; D051764:PAX9 Transcription Factor; C497323:PAX9 protein, human; D008156:Luciferases