In this study, we observed that MTHFR rs1801133 was associated with serum Hcy levels in patients with epilepsy (CC vs. CT vs. TT: 12.4 ± 5.01 vs. 13.44 ± 4.79 vs. 19.92 ± 15.39 μmol/l, P < 0.001), with the TT genotype resulting in higher serum Hcy levels than the CC (P < 0.001) or CT (P < 0.001) genotype (Table 2). This evidence concerns the gene MTHFR and epilepsy.