Studies for the genotyping of MMPs seem to be much advanced than those for TIMPs. For example, in 2012 Liu and his colleagues performed a meta-analysis exploring the association between MMP1 promoter -1607 1G/2G polymorphism and the risk of several types of cancer, and the results showed that an elevated risk of cancer was found regarding breast cancer and other types of cancer such as colorectal cancer and genitourinary neoplasm [13]. Here, MMP1 is linked to cancer.