Polymorphisms in CHDH gene and the risk of tooth agenesis.

Background: Tooth agenesis is one of the most common anomalies of human dentition and is due to a complex and not fully elucidated etiology. The purpose of this study was to evaluate the possibility that polymorphic variants of genes encoding the main folate and choline metabolism enzymes might be associated with the risk of hypodontia in the Polish population.
Methods and Results: We analyzed 21 polymorphisms of 13 candidate genes and found that single nucleotide polymorphisms (SNPs) in the CHDH gene are significantly correlated with the risk of dental agenesis. The strongest association was found for the SNP located in the intronic sequence of CHDH. Individuals carrying one copy of the rs6445606 C allele had an over two-fold decreased risk of having hypodontia (odds ratio [OR]CTvsTT=0.434; 95% confidence interval [CI], 0.2724-0.6915; p=0.0004; pcorr=0.0084). A reduced risk of tooth agenesis was also observed in individuals with one or two copies of the rs6445606 C allele compared to T allele carriers (ORCT+CCvsTT=0.524; 95% CI, 0.3386-0.8097; p=0.0035; pcorr=0.0735). Moreover, the gene-gene interaction analysis revealed a significant epistatic interaction between CHDH (rs6445606) and PLD2 (rs3764897) in the susceptibility to hypodontia (p=0.004).
Conclusion: Our study identified CHDH and PLD2 as novel candidate genes, the nucleotide variants of which could be associated with the risk of tooth agenesis.
(Copyright © 2011 Wiley-Liss, Inc.)