The guidelines of both European Association for the Study of Diabetes (EASD) and the American Diabetes Association (ADA) recommend SGLT-2 inhibitors as a combination therapy with other antihyperglycemic drugs at any stage of T2DM and when metformin is not tolerated or ineffective, SGLT-2 inhibitors was recommend as an acceptable alternative to metformin [7–8]. The gene discussed is SLC5A2; the disease is type 2 diabetes mellitus.