Here, we show that decreased PNMT expression in the PHD2-deficient adrenal medulla reduces epinephrine synthesis, but systemic effects in these PHD2-deficient mice, such as enhanced EPO production, consequent RBC excess, and hypoglycemia, lead to enhanced secretion of this hormone from the adrenal gland (Fig. 6). The gene discussed is EPO; the disease is Hypoglycemia.