Q. 7.  Based on your understanding of genetic code, explain the formation of any abnormal hemoglobin molecule. What are the known consequences of such a change?

Due to point mutation in β-globin chain of the hemoglobin molecule, glutamic acid (Glu) is replaced by valine (Val) at the sixth position.

Under stress condition erythrocytes lose their circular shape and become sickle-shaped. As a result, the cells cannot pass through narrow capillaries. Blood capillaries are clogged and thus affect blood supply to different organs.