Since the pathophysiology underlying T2D is characterized by defective insulin secretion and reduced insulin sensitivity, a cross-section study was designed to determine beta-cell secretory function and insulin sensitivity in the three KCNB1 rs1051295 variants under basal (fasting) condition to assess which of these traits could account for their differential risk for T2D. The gene discussed is INS; the disease is type 2 diabetes mellitus.