Hi.. Individuals with beta thalassemia trait usually have evidence of microcytosis and increased levels of hemoglobin A2. Hemoglobin F is sometimes elevated as well. Individuals with alpha thalassemia trait usually have evidence of microcytosis and normal levels of hemoglobin A2 and F. Sometimes trait status cannot be determined by these screening tests alone. Results may be ambiguous for a variety of reasons. If iron deficiency is detected, an individual must be retested after completing iron supplement therapy. Occasionally, DNA testing that directly examines the alpha and/or beta globin genes is necessary. DNA testing is the only way to determine silent… Read more »