It is known that dhps deficiency (the gene encoding DHS) or chronic treatment with DHS inhibitors, as GC7, ameliorate glucose tolerance and glycaemia in various mouse models of diabetes (HFD30,31, STZ9,32, humanized mouse model of T1D33, db/db29; NOD34). The gene discussed is DHPS; the disease is hyperinsulinemic hypoglycemia, familial, 4.