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

Abstract

Our research aimed to look into the clinical traits and genetic mutations in sporadic non-syndromic anodontia and to gain insight into the role of mutations of PAX9, MSX1, AXIN2 and EDA in anodontia phenotypes, especially for the PAX9.Material and Methods:The female proband and her family members from the ethnic Han families underwent complete oral examinations and received a retrospective review. Venous blood samples were obtained to screen variants in the PAX9, MSX1, AXIN2, and EDA genes. A case-control study was performed on 50 subjects with sporadic tooth agenesis (cases) and 100 healthy controls, which genotyped a PAX9 gene polymorphism (rs4904210). Results:Intra-oral and panoramic radiographs revealed that the female proband had anodontia denoted by the complete absence of teeth in both the primary and secondary dentitions, while all her family members maintained normal dentitions. Detected in the female proband were variants of the PAX9 and AXIN2 including A240P (rs4904210) of the PAX9, c.148C>T (rs2240308), c.1365A>G (rs9915936) and c.1386C>T (rs1133683) of the AXIN2. The same variants were present in her unaffected younger brother. The PAX9 variations were in a different state in her parents. Mutations in the MSX1 and EDA genes were not identified. No significant diferences were found in the allele and genotype frequencies of the PAX9 polymorphism between the controls and the subjects with sporadic tooth agenesis. Conclusions:These results suggest that the association of A240P with sporadic tooth agenesis still remains obscure, especially for different populations. The genotype/phenotype correlation in congenital anodontia should be verified.

Genetic study of non‐syndromic tooth agenesis through the screening of paired box 9, msh homeobox 1, axin 2, and Wnt family member 10A genes: a case‐series

“…With respect to sequencing of the PAX9 gene, only one missense variant (p.Ala240Pro) was identified and, according to the results of the chi‐square test (Table ), it was not a risk factor for isolated tooth agenesis in our study population. Several association studies have demonstrated that this variant does not predispose for tooth agenesis in a southern Chinese population , although another study has positively associated this variant with tooth agenesis in the same ethnic population . Other studies in different ethnic populations have considered that this variant is probably a polymorphism .…”

PAX9 gene mutations and tooth agenesis: A review

“…Complicating the matter even further, the rs4904210 polymorphism was the only change found in 1 Chinese Han family represented by 6 individuals with no mutation in MSX1 gene and AXIN2 gene leading to a conclusion that Ala240Pro substitution (rs4904210 polymorphism) could be a risk factor for tooth agenesis in Han ethnicity . Wang et al studied sporadic anodontia in Han family consisting of 3 healthy members and a female proband with complete absence of primary and secondary dentitions. They found the rs4904210 polymorphism in the heterozygous state in the female proband and her younger brother and the homozygous genotype CC in her father but not in her mother.…”

“…Zhang et al performed meta‐analysis of the data chosen from 4 previous studies related to the rs4904210 polymorphism; Pinho et al, Paixão‐Côrtes et al, Liu et al and Wang et al Their results showed no significant association between hypodontia and the g.13981G>C polymorphism (rs4904210).…”

PAX-9 polymorphism may be a risk factor for hypodontia: a meta-analysis

“…According to the inclusion criteria, 6 studies (Peres et al, 2005;Pawlowska et al, 2010;Pinho et al, 2010;Paixão-Côrtes et al, 2011;Liu et al, 2012;Wang et al, 2013) were included in the meta-analysis and 96 were excluded. The flow chart of study selection is shown in Figure 1.…”