An ongoing Glycemia Reduction Approaches in Diabetes: A Comparative Effectiveness Study (GRADE) has compared the effect of four major drug classes (sulfonylurea, DPP-4 inhibitor, GLP-1 analog, and basal insulin) over 4 years on glycemic control and other psychosocial, medical, and health economic outcomes (34). The gene discussed is DPP4; the disease is diabetes mellitus.