Therefore, considering the limited and contradictory clinical evidence reporting the therapeutic effects of DPP-4 inhibitors, especially linagliptin, on diabetic nephropathy in patients with T2D, this study aimed to investigate the effect of linagliptin on microalbuminuria as a key step in preventing the progression of diabetic nephropathy in patients with T2D. The gene discussed is DPP4; the disease is type 2 diabetes mellitus.