Analysis of the association between polymorphisms in Vitamin D receptor gene and dental caries

The influence of environmental factors on dental caries is a well-established fact; however, little is known about the impact of genetics on the caries process.

This study was aimed to analyse the association between the vitamin D receptor (VDR) gene polymorphism and dental caries. It also compared the risk of dental caries between individuals with homozygous (tt and TT) genotype and heterozygous (Tt) genotype. Further, this study also aimed to compare VDR gene polymorphism by gender.

A total of 196 subjects were selected based on their decayed, missing, filled teeth (DMFT) index according to the WHO guidelines (1997), and were divided into two groups based on caries experience. The case group was further classified into low and high caries groups. The saliva samples were collected, DNA was extracted, and VDR Taq1 (T/C) gene polymorphism was analysed by polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) and visualized under 2% agarose gel.

There was no significant difference in the VDR Taq1 polymorphism and dental caries between the case and control group. However, further stratification showed a statistically significant difference based on caries experience in the study group. The heterozygous mutant genotype (Tt) was associated with a higher caries experience (62.1%) (P = 0.008) with the frequency of 't' allele being 77% as compared to 'T' allele (63.6%) in the high caries group.

VDR Taq1 gene polymorphism does not seem to have a role in the incidence of dental caries in the studied population; however, it may have a role in the severity of the caries process.