Enamel Microhardness Analysis Suggests Genetic Influences in Caries

Objectives: Genetic association studies of caries have suggested that variation in enamel formation genes may contribute to caries susceptibility. The goal of this study was to evaluate if genetic variation is associated with enamel microhardness in human premolars.
Methods: In this study, enamel samples from premolars of 53 individuals were analyzed for Knoop hardness indentation length of sound enamel, integrated mineral loss after carious lesion creation, and change in integrated mineral loss after remineralization. DNA from these 53 individuals was collected, and 36 single nucleotide polymorphism markers were genotyped. Chi-square and Fischer exact tests (alpha of 0.05) were used in the investigation of overrepresentation of alleles or genotypes. For each variable (Knoop hardness indentation length of sound enamel, integrated mineral loss after carious lesion creation, and change in integrated mineral loss after remineralization), the samples were divided into two groups based on having a value above or below the mean of the cohort studied.
Results: An association between the integrated mineral loss after carious lesion creation and marker rs3759129 in aquaporin (AQP5, p=0.03), markers rs7526319 (p=0.02) and rs2337360 (p=0.04) in tuftelin (TUFT1), and marker rs6862039 in basic transcription factor (BTF3, p=0.01) was discovered.
Conclusions: The results suggest that genetic variation in several genes influences the caries process in enamel.