Question

Which disorder is caused by the substitution of Glutamic acid (Glu) by Valine (Val) at the sixth position of the beta globin chain of the hemoglobin?

• A. Phenylketonuria
• B. Sickle-cell Anemia
• C. Hemophilia
• D. Thalassemia

Answer 1

The Correct Option is B

Sickle-cell anemia is a genetic disorder caused by a point mutation in the hemoglobin-beta gene. This mutation leads to the substitution of Glutamic acid (Glu) with Valine (Val) at the sixth position of the beta globin chain. This single amino acid change causes hemoglobin to form fibers, leading to the characteristic sickle shape of red blood cells.

Answer 2

Sickle-cell anemia is a genetic disorder caused by a mutation in the beta-globin gene of hemoglobin. Specifically, it involves the substitution of the amino acid glutamic acid (Glu) with valine (Val) at the sixth position of the beta-globin chain. This small change leads to the formation of abnormal hemoglobin, known as hemoglobin S (HbS), which causes red blood cells to adopt a sickle shape, leading to reduced oxygen-carrying capacity and blockages in blood vessels.

• Phenylketonuria is caused by a defect in the enzyme phenylalanine hydroxylase.
• Hemophilia is a bleeding disorder caused by a deficiency in clotting factors.
• Thalassemia involves reduced or absent production of one of the globin chains of hemoglobin, but it does not result from the glutamic acid to valine substitution.