Although our study did not reveal correlation between MMP3–1612 6A/5A, MMP12 -82A/G polymorphisms and RHD in Han population, studies have shown a combined effect of MMP1–1607 1G/2G, MMP3–1612 6A/5A and MMP12-82A/G polymorphisms associated with esophageal adenocarcinoma (EA) risk in Caucasian [30]. This evidence concerns the gene MMP1 and esophageal adenocarcinoma.