Anemias USMLE Step 1 Practice Question
A 16 year old African American boy presents with severe pain in both legs and shortness of breath after a viral illness. He has had recurrent painful episodes since childhood and was hospitalized at age 3 for hand swelling. Examination shows scleral icterus. Peripheral smear demonstrates sickled erythrocytes. Which of the following substitutions is responsible for this patient's disease?
Answer choices
- AGlutamate to lysine in the beta globin chain
- BLysine to glutamate in the alpha globin chain
- CValine to glutamate in the beta globin chain
- DDeletion of 2 alpha globin genes
- EGlutamate to valine in the beta globin chainCorrect answer
- FAlpha-thalassemia trait
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