RSAD2 and in situ carcinoma: MR analysis (Supporting Information 1: Tables S6–9, Figure 7a,b, Supporting Information 2: Figure S4a,b) uncovered a causal connection between decreased RSAD2 expression and a higher risk of HSIL (IVW odds ratio [OR] = 0.80, 95% CI 0.68–0.94, padj = 7.96 × 10−3) and CIS (IVW OR = 0.71, 95% CI 0.50–0.99, padj = 4.93 × 10−2), with no evidence of heterogeneity (Cochran's Q p > 0.05) or pleiotropy (pGlobal > 0.05, pIntercept > 0.05).