Univariate logistic regression analysis showed that patients with MMP1 rs1799750 1G1G (versus 2G2G) genotype and 2G allele noncarriers (versus carriers) were predisposed to lower rates of poorly differentiated BC (OR = 0.095, 95% CI 0.022–0.406, p = 0.001, and OR = 0.176, 95% CI 0.038–0.810, p = 0.026, respectively). This evidence concerns the gene MMP1 and breast cancer.