Question

Sickle cell anaemia is

• A. An autosomal linked dominant trait
• B. Caused by substitution of valine by glutamic acid in the $\beta$-globin chain of haemoglobin
• C. Caused by a change in base pair of DNA
• D. Characterized by elongated sickle like RBCs with a nucleus

Answer 1

Answer: (B)

Caused by substitution of valine by glutamic acid in the $\beta$-globin chain of haemoglobin

Sickle-cell anaemia is caused by a change in a single base pair of DNA (substitution of valine by glutamic acid in the β-globin chain of haemoglobin). It is a genetic disease. The individuals suffering from sickle-cell anaemia are immune to malaria. Thus, option B is correct.