HAMP and myelodysplastic syndrome with single lineage dysplasia: Although the hepcidin/ferritin ratio showed a generalized trend toward a relatively inappropriate response, the homeostatic control by iron appeared relatively conserved in MDS subtypes generally considered at low risk (like RA, RARS and the 5q- syndrome), while it appeared almost completely lost in conditions prominent dysmyelopoiesis like RAEB and CMML.