A study on the relationship between cheese intake and caries occurrence based on Mendelian randomization method

Objective: The study aims to investigate the causal relationship between cheese intake and caries occurrence by a two-sample Mendelian randomization method (TSMR). Methods: Data from a genome-wide association study (GWAS) on cheese intake as an exposure factor were collected, and dental caries was the outcome variable, appropriate SNPs were selected as instrumental variables (IVs). The TSMR was analyzed by the inverse variance weighting (IVW) method, weighted median method, MR-Egger regression method, simple model and weighted model. Results: We identified forty-four single-nucleotide polymorphisms (SNPs) in the gene encoding group-specific component (cheese) that were associated with cheese intake, and IVW was adopted. The IVW method supported a relationship between cheese intake and the risk of dental caries occurrence[OR,1.00(95 %CI,0.99-1.00), P = 0.039 < 0.05]. There was no horizontal pleiotropy between the IVs(b = -0.0037, P = 0.39), and the sensitivity analysis using the "leaveone-out" method was robust to causal effects. Conclusion: The results of the TSMR analysis supported that an appropriate intake of cheese could reduce the occurrence of dental caries.