HAMP and anemia (phenotype): Elevations in erythropoiesis and mild anemia likely cause an increase in the expression of the bone marrow‐derived hormone erythroferrone, which acts to suppress expression of hepcidin.10 This represents a milder phenotype to the condition seen in homozygote or compound heterozygote thalassemia conditions.27 We were concerned that suppression of hepcidin in patients carrying thalassemia could impair its utility to detect iron deficiency in the same population.