HBA2 and thalassemia: If the microcytic hypochromic parameters persist in a patient with normal levels of ferritin or Zinc Protoporphyrin (ZPP, a measure for long-lasting iron depletion), elevated RBC and normal (or low) HbA2, (especially in patients originating from areas where haemoglobinopathies are common) there is a good chance that the individual is a carrier of α-thalassaemia.