Question

Sickle cell anemia is due to

• A. Change of amino acid in alpha chain of hemoglobin
  
• B. Change of the amino acid in beta chain of hemoglobin
• C. Change of amino acid in both alpha and beta chain of hemoglobin
• D. Change of amino acid either alpha or beta chain of hemoglobin

Answer 1

The correct option is B Change of the amino acid in beta chain of hemoglobin

The sickle cell mutation reflects a single change in the amino acid building blocks of the oxygen-transport protein, hemoglobin. This protein, which is the component that gives red cells their color, has two subunits. The alpha subunit is normal in people with sickle cell disease. The beta subunit has the amino acid valine at position 6 instead of the glutamic acid that is normally present. The alteration is the basis of all the problems that occur in people with sickle cell disease.