In another study, the methylation status of a panel of genes that are closely related (MMP2, MMP9, TIMP2, AKR1B1, MYL9, SCL2A4, SCL2A1 and SCL4A3), which were known to be involved in kidney development or diabetic kidney disease or those associated with dialysis-induced changes in gene expression in peripheral blood cells [211], has been studied in T2D patients with or without DN. Here, MMP9 is linked to type 2 diabetes mellitus.