Objectives: The aim of this study was investigate the association between genetic polymorphisms in ESR1, ESR2, and ESRRB and dental fluorosis (DF) in a well-characterized sample of children from Curitiba, Brazil.
Material and methods: From a representative sample of 538 children, 12-year-old were evaluated. DF was assessed in erupted permanent teeth by the Dean's index modified. Fourteen polymorphisms were selected in intronic and intergenic regions of ESR1, ESR2, and ESRRB and genotyped in genomic DNA source from saliva using TaqMan chemistry and end-point analysis. Allele and genotype distributions between DF and DF free groups were analyzed using the Epi Info 7.2. Chi-square or Fisher's exact tests at a level of significance of 5% and odds ratios calculations with 95% confidence intervals were used to determine the statistical associations.
Results: Among 538 children, 147 were DF and 391 were DF free. Genotype distribution for the polymorphism rs12154178 in ESR1 was different between the two groups (p = 0.037; OR = 0.91; CI = 0.67-1.22). The dominant model analysis (AA+AC vs. CC) demonstrated that CC is a protective factor for DF (p = 0.038; OR = 0.51, 0.27-0.97 95% CI). We did not find differences in frequency distributions in the other evaluated polymorphisms.
Conclusion: This study provides evidence that ESR1 is associated with DF.
Clinical relevance: Dental fluorosis is an important condition that affects the mineralized tissues of the teeth. In severe cases, the treatment takes time and is extremely costly. This research provides evidences that there are genetic factors involved in dental fluorosis and will help professionals to plan more precise strategies to reduce dental fluorosis occurrence.
Keywords: Dental fluorosis; Estrogen receptor gene; Polymorphism.