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?
- A)Glutamate to lysine in the beta globin chain
- B)Lysine to glutamate in the alpha globin chain
- C)Valine to glutamate in the beta globin chain
- D)Deletion of 2 alpha globin genes
- E)Glutamate to valine in the beta globin chainGABARITO
Explicação
Glutamate to valine in the beta globin chain is correct. Sickle cell disease results from a missense mutation in beta globin that creates hemoglobin S. Deoxygenated hemoglobin S polymerizes, leading to red cell deformation, chronic hemolysis, painful vaso occl... Ver explicação completa e trilha adaptativa →