We conducted stratification analysis by depression status in the case and control groups (Table 6), and this revealed an association between depression risk and MTHFR rs1801133 genotypes in the controls (in codominant model CC vs. TT: OR = 3.39, 95%: 1.49–7.74, p = 0.011) but not in women with gynecologic cancers. Here, MTHFR is linked to major depressive disorder.