In MR analyses using the weighted median method, the SCGFb level remains negatively associated with PCOS (OR = 1.879, 95% CI = 1.182 – 2.987, P = 0.008); the SDF1a level remains positively associated with PCOS (OR = 0.768, 95% CI = 0.617 – 0.956, P = 0.018), but the IL-4 level is not significantly associated with PCOS (OR = 0.722, 95% CI = 0.419 – 1.243, P = 0.240). The gene discussed is CXCL12; the disease is polycystic ovary syndrome.