Sickle cell anemia-hereditary disease-polypeptide chains

Question

In the sickle cell anemia, hereditary disease, there is swap of one amino acid through another in one of the four polypeptide chains of hemoglobin. In this situation are all of the structural levels of protein modified?

Answer 1

In the sickle cell disease there is an alteration in primary protein structure of one of polypeptide chains which form hemoglobin: amino acid glutamic acid is substituted through the amino acid valine in β chain. The spatial conformation of molecule additionally is also influenced and modified through this primary ‘mistake’ and the modification as well makes a different (sickle) shape to red blood cells. Modified, or sickled, red blood cells sometimes cumulative and obstruct peripheral circulation causing tissue hypoxia as well as pain crisis typical of sickle cell anemia.