As shown in Figure 2, MR revealed causal relationships between 8immune phenotypes and meningioma, comprising 2 risk factors and 6 protective factors Among these, B cell-related phenotypes included CD20 on IgD − CD24 − B cell (P = .048, OR = 1.094, 95% CI = 1.001 − 1.196), CD38 on IgD − CD38 + B cell (P = .004, OR = 0.949, 95% CI = 0.915 − 0.984), and CD38 on IgD − CD38dim B cell (P = .02, OR = 1.073, 95% CI = 1.011 − 1.140). This evidence concerns the gene CD38 and meningioma.