Question

Sickle-cell anemia trait is an adaptation against malaria. It is due to substitution (point mutation) in which

• A. Instead of an acidic amino acid valine, a neutral amino acid valine comes at the number 6^th position in one of the $β-$ chain of Hb.
• B. Instead of neutral amino acid valine, acidic amino acid glutamic acid is inserted at the number 6^th position of $\beta $ chain Hb.
• C. Instead of neutral amino acid glutamic acid, an acidic amino acid valine comes at 6^th position in one of the β-chain of Hb.
• D. Instead of an acidic amino acid glutamic acid, a neutral amino acid valine comes at 6^th position in one of the β-chain of Hb.

Answer 1

Answer: (D)

Sickle-cell anemia is a qualitative blood disorder, which is controlled by the recessive autosomal gene. In this change in single nucleotide in DNA sequence results in change in 6^th amino acid of β-chain of Hb.