It is controversial as to whether there is a significant association between glucagon levels and glycemic control, as Knop et al. and Yoshiya et al. also validated our findings and suggested that fasting glucagon was not correlated with the FPG concentration in people with diabetes and impaired glucose tolerance, and, therefore, similar in diabetic and non-diabetic subjects [23,24]. The gene discussed is GCG; the disease is Impaired glucose tolerance.