Sideroblastic anemia is a form of anemia caused by an inability to incorporate iron into hemoglobin, something that is essential if the molecule is to perform its vital function of carrying oxygen from the lungs to the tissues. Recently, a patient with sideroblastic anemia was found to have a mutation in their GLRX5 gene that led to GLRX5 protein deficiency. New research has now provided insight into how GLRX5 protein deficiency causes sideroblastic anemia.