On the contrary, signs that point out to GCK-MODY in patients with already established diagnosis of diabetes (labeled falsely as type 1 or type 2), in our opinion, include non-progressive character of glycaemic disorder (relatively stable glycaemia and HbA1c), non-decreasing (normal) endogenous insulin secretion, low efficacy of oral antidiabetics (e.g., metformin) administered or relatively low doses of insulin required and absence of vascular complications after many years of diabetes duration. Here, INS is linked to diabetes mellitus.