Polymorphisms in OCT1 or MATE1 have been correlated with the susceptibility of type 2 diabetes, diabetic nephropathy, hypertension, and primary biliary cirrhosis [26–28]. SLC47A1 rs2453583 and SLC22A1 rs651154 have been reported to be nominally associated with diabetes incidence in the DPP (Diabetes Prevention Program) [26]. Here, SLC22A1 is linked to type 2 diabetes mellitus.