None of the models showed a significant association between the TGF-β1-509 C/T polymorphism and BC risk (Combined analysis: overall allele (OR)  =  0.986, 95% CI = 0.923–1.053, p = 0.676; homozygous: OR = 0.971, 95% CI = 0.836–1.127, p = 0.696; heterozygous: OR = 0.986, 95% CI = 0.936–1.039, p = 0.594; recessive: OR = 0.985, 95% CI = 0.912–1.064, p = 0.706; dominant: OR = 0.984, 95% CI = 0.937–1.034, p = 0.527) (Figure 3). The gene discussed is TGFB1; the disease is breast cancer.