During the T2D course, metformin (54.7% vs. 46.3%, P < 0.001) and thiazolidinediones (19.1% vs. 13.1%, P < 0.001) were prescribed more frequently among early-onset patients, and insulin was prescribed more frequently for late-onset T2D patients (42.0% vs. 36.1%, P < 0.001). The gene discussed is INS; the disease is type 2 diabetes mellitus.