Sequence analysis of PAX9, MSX1 and AXIN2 genes in a Chinese oligodontia family.

The goal of our research was to look into the clinical traits and genetic mutations in nonsyndromic oligodontia in a Chinese family and to gain insight into the role of mutations of PAX9, MSX1 and AXIN2 in oligodontia phenotypes. 6 subjects from a family underwent complete oral examination, including panoramic radiographs. Retrospective data were reviewed and blood samples were collected. PCR primers for PAX9, MSX1, and AXIN2 were designed through the Oligo Primer Analysis Software. PCR products were purified and sequenced using the BigDye Terminator Kit and analysed by the 3730 DNA Analyzer. The proband missed 4 permanent canines, 2 permanent maxillary lateral incisors, 2 permanent mandibular lateral incisors, and 2 permanent mandibular central incisors, whilst his maternal grandfather lacked only 2 permanent mandibular central incisors. Moreover, the size of some permanent teeth appeared smaller than normal values of crown width of Chinese people. Oligodontia and abnormalities of teeth were not present in other family members. Radiographic examination showed that the proband and the rest of family members retained all germs of the third molars. There was one known mutation A240P (rs4904210) of PAX9 in the coding region in the proband and the maternal family members (II-2, II-3, and II-4), which possibly contributed to structural and functional changes of proteins. No mutations were identified in MSX1 and AXIN2. Our findings may imply that the PAX9 A240P mutation is a risk factor for oligodontia in the Chinese population. A240P is likely to be a genetic cause of oligodontia though previous literature suggested it as a polymorphism only.

Wang J ，Jian F ，Chen J ，Wang H ，Lin Y ，Yang Z ，Pan X ，Lai W ... -  《-》

PAX9 polymorphism and susceptibility to sporadic non-syndromic severe anodontia: a case-control study in southwest China.

Wang J ，Xu Y ，Chen J ，Wang F ，Huang R ，Wu S ，Shu L ，Qiu J ，Yang Z ，Xue J ，Wang R ，Zhao J ，Lai W ... -  《-》

Exclusion of coding region mutations in MSX1, PAX9 and AXIN2 in eight patients with severe oligodontia phenotype.

Gerits A ，Nieminen P ，De Muynck S ，Carels C ... -  《Orthodontics & Craniofacial Research》

Clinical and genetic evaluation of a Chinese family with isolated oligodontia.

Oligodontia is defined as the congenital absence of 6 or more permanent teeth excluding the third molar. Tooth agenesis may be classified as syndromic/non-syndromic and as familial/sporadic. To date, more than 300 genes have been found to be involved in tooth development, but only a few of these genes, such as MSX1, PAX9 and AXIN2, are related to the condition of non-syndromic oligodontia. The objective of the present work was to investigate the disease-causing gene of non-syndromic oligodontia in a Han Chinese family and analyse the pathogenesis of mutations that result in oligodontia. We examined all individuals of the oligodontia family by clinical and radiographic examinations. Based on the clinical manifestations, the candidate genes MSX, PAX9 and AXIN2 were selected to analyse and screen for mutations. The clinical evaluation suggested that the family might show non-syndromic oligodontia. DNA sequencing of the MSX1 gene revealed two mutations in the two patients with oligodontia: a heterozygotic silent mutation, c.348C>T (P.Gly116=), in exon 1 and a homozygotic deletion of 11 nucleotides (c.469+56delins GCCGGGTGGGG) in the intron. However, the silent mutation and the deletion mutation were thought to be known polymorphisms (rs34165410 and rs34341187) by bioinformatics analysis. We did not detect any mutations in the PAX9 and AXIN2 genes of oligodontia patients. Our finding suggests that identified polymorphisms (c.348C>T and c.469+56delins GCCGGGTGGGG) may be responsible for the oligodontia phenotype in this Chinese family, but the association requires further study.

Qin H ，Xu HZ ，Xuan K 《-》

Mutational analysis of AXIN2, MSX1, and PAX9 in two Mexican oligodontia families.

Mu YD ，Xu Z ，Contreras CI ，McDaniel JS ，Donly KJ ，Chen S ... -  《Genetics and Molecular Research》