Blunted hyperinsulinemia and improved glucose andinsulin tolerance following 2-hour fasting suggested initiallythat HFD-fed Ppara-null mice are protected from insulinresistance (IR) as a result of either reduced hepatic glucoseproduction or increased peripheral insulin sensitivity [20].However, this report has been contested by a study that foundlittle difference in hyperinsulinemia and peripheral glucoseuptake during euglycemic clamp of HFD-fed wt versusPpara-null mice in the nonfasted state [23]. The gene discussed is PPARA; the disease is hyperinsulinism.