Erythroid precursors that have accumulated abnormal amounts of iron are called ringed sideroblasts. Sideroblastic anemia can be either inherited or acquired. Common acquired causes are ingestion of certain drugs, alcohol, or toxins such as lead or zinc. The beta-thalassemia trait is diagnosed by demonstrating an elevated HbA2, iron deficiency by iron studies and ferritin levels, and anemia of chronic disease by demonstrating a chronic disease. Sideroblastic anemia generally requires a bone marrow aspiration revealing ringed sideroblasts for diagnosis.