SLC5A1 and type 2 diabetes mellitus: Furthermore, there is increasing evidence that transportprotein malfunction also plays a role in more common complex diseasessuch as cancer and diabetes., For example, the glucosetransporters SLC5A1/SGLT1 and SLC5A2/SGLT2,, as well as the zinc transport protein SLC30A8,, are closely linked to type 1 and type 2 diabetes.