As for the subgroup analysis results of PTH and T2D, the summary OR for cohort studies was 1.04 (95% CI: 1.00–1.08; P = 0.133) and for cross-sectional studies was 0.99 (95% CI: 0.97–1.01; P = 0.431). This evidence concerns the gene PTH and type 2 diabetes mellitus.