As a result, the summary ORs remained unchanged, despite deleting one single study, the first studies, or deviations from HWE among controls, with the only exception of MMP-2 rs243865 with NPC risk among the Asian populations in dominant model, MMP-7 rs11568818 with CC risk in Asians under the dominant model, and MMP-9 rs3918242 with LC risk among the overall populations in the recessive model and with BC risk among the overall populations in the dominant model. The gene discussed is MMP9; the disease is breast cancer.