The C allele of EZH2 rs12670401 (odds ratio (OR) =1.255, 95% confidence interval (95% CI): 1.085–1.452), T allele of EZH2 rs6464926 (OR =1.240, 95% CI: 1.071–1.435), and three alleles of SMYD3 variable number of tandem repeats (VNTRs) (OR =1.305, 95% CI: 1.097–1.552) could increase susceptibility to breast cancer. The gene discussed is SMYD3; the disease is breast cancer.