Association between DEFB1 rs11362 and Caries Susceptibility in Permanent Dentition: A Cross Sectional Study

Dental caries is a multifactorial chronic bacterial infectious disease. Variations in the predisposition of the general population to dental cavities suggest that genetic and immunological factors play significant roles in its pathogenesis. This study aims to explore the impact of the Beta-Defensin 1 (DEFB1) rs11362 polymorphism on caries susceptibility in permanent dentition among the Bai Kuyao and Zhuang ethnic groups in China.

A sample of 754 adolescents aged 12-15 was randomly selected from primary and junior high schools in Nandan County, Guangxi, China. All adolescents underwent clinical examinations, and DNA samples were collected. The genotype of DEFB1 rs11362 was determined using single nucleotide polymorphism (SNP) typing. The concentration of human β Defensin 1 (hBD-1) protein in saliva was measured using a double-antibody sandwich enzyme-linked immunosorbent assay (ELISA).

The distribution of the DEFB1 rs11362 T allele was lower in the Bai Kuyao group compared to the Zhuang group. The disparity in the rs11362 genotype was statistically significant in the superficial dentin caries subgroup of the Bai Kuyao population (p = 0.017). Following adjustment for all potential confounding variables, the analysis revealed a heightened risk of superficial dental caries among CT genotype carriers in the Bai Kuyao population under a co-dominant model (odds ratios (OR) = 2.70; 95% confidence intervals (CI) [1.35-5.44]; p = 0.005), and an increased risk among CC genotype carriers in the Bai Kuyao population under a dominant model (OR = 2.35; 95% CI [1.18-4.67]; p = 0.015). A significant difference (p < 0.05) was noted in the distribution of rs11362 genotypes and salivary hBD-1 levels among the Bai Kuyao group. Salivary hBD-1 levels were notably higher in the CC genotype group (4.12 ± 2.07 ng/mL) compared to both the CT (2.77 ± 1.62 ng/mL) and TT genotype groups (2.32 ± 0.98 ng/mL).

The DEFB1 rs11362 polymorphism showed an association with caries susceptibility in permanent teeth and influenced hBD-1 protein expression in saliva. Consequently, the DEFB1 polymorphism likely represents a concealed risk factor for caries.