Testing for abnormal hemoglobins may initially be performed using high pressure liquid chromatography (HPLC) as shown above left, with results typical for sickle cell anemia in which over 90% of the hemoglobin is Hgb S. The HPLC findings may be confirmed for the more common hemoglobinopathies by hemoglobin electrophoresis, as shown above right. In this example, patient 1 has sickle cell anemia, patient 2 hemoglobin C disease, patient 3 hemoglobin C trait, and patient 4 sickle cell trait.

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