Association between Vitamin D Receptor Gene Polymorphisms and Periodontal Bacteria: A Clinical Pilot Study

Abstract: Background: Periodontitis is an inflammatory disease caused by microorganisms involving the supporting tissues of the teeth. Gene variants may influence both the composition of the\r\nbiofilm in the oral cavity and the host response. The objective of the study was to investigate the\r\npotential correlations between the disease susceptibility, the presence and the quantity of periodontopathogenic oral bacterial composition and the VDR gene polymorphisms. Methods: Fifty (50)\r\nunrelated periodontal patients and forty-one (41) healthy controls were selected for genomic DNA\r\nextraction. DNA concentration was measured and analyzed. The periodontopathogenic bacterial\r\nspecies were identified and quantified using a Real Time PCR performed with species-specific primers\r\nand probes. Results: Genotype distribution showed a different distribution between the groups for\r\nBsmI rs1544410 genotypes (p = 0.0001) with a prevalence of the G(b) allele in periodontal patients\r\n(p = 0.0003). Statistical significance was also found for VDR TaqI rs731236 (p ≤ 0.00001) with a\r\nprevalence of the T(T) allele in periodontal patients (p ≤ 0.00001). The average bacterial copy count\r\nfor the periodontitis group was significantly higher than that of control group. Dividing patients\r\ninto two groups based on high or low bacterial load, FokI rs2228570 T allele (f) was statistically more\r\nrepresented in patients with high bacterial load. Conclusions: The findings of the study suggest the\r\ninvolvement of the VDR gene BsmI and TaqI polymorphisms in periodontal disease, while FokI and\r\nBsmI may be involved in determining an increased presence of periodontopathogens.