Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and meta-analysis

Background To investigate the association of vitamin D receptor (VDR) gene polymorphism with caries risk in children(< 18 years). Methods The electronic databases PubMed, Cochrane, EMBASE, Web of Science, CNKI, Cqvip, and Wanfang were searched for observational studies on the relationship between VDR single nucleotide polymorphism(SNP) and caries, including cohort, case-control, and cross-sectional studies. Quality assessment of selected studies was conducted using the Newcastle Ottawa scale. Odds ratios (OR) with 95% confidence intervals (CI) values for associations of individual VDR SNP with dental caries were calculated based on four genetic models: allelic, recessive, dominant, and over-dominant. Results Of 79 studies considered, 10 (nine case-control and one cross-sectional) were selected for analysis; the studies involved seven VDR SNPs: ApaI(rs7975232),BsmI(rs1544410),FokI(rs2228570),TaqI(rs731236), TaqI/BglI(rs739837), FokI(rs10735810) and Cdx-2(rs11568820). Alleles C and T of FokI(rs10735810) were significantly differently distributed in the caries and caries-free groups (OR = 1.33, 95% CI: 1.30-2.30, P = 0.03), with CC + CT genotypes at this locus associated with greater risk of developing caries than the TT genotype (OR = 1.87, 95%CI: 1.15-3.04, P = 0.01). Further, TT + CC genotype at TaqI(rs731236) was associated with a 1.33-fold higher risk of caries development than the TC genotype (OR = 1.33, 95%CI: 1.06-1.67, P = 0.02). On subgroup analysis, the association between TaqI(rs731236) and caries risk was affected by dentition type, and ethnicity (permanent dentition: OR = 1.48, 95%CI: 1.07-2.03, P = 0.02; Asian: OR = 1.38, 95%CI: 1.02-1.87, P = 0.03;). Genotype distributions at BsmI(rs1544410), TaqI/BglI(rs739837), FokI(rs2228570), and ApaI(rs7975232) did not differ significantly between the caries and caries-free groups. Conclusions Caries risk could be associated with TaqI(rs731236) and FokI(rs10735810) genotypes, and TaqI(rs731236) may be a risk factor for permanent teeth caries among Asian people.