NEET 2026 (Phase 1) · BiologyPrevious Year Question
The sixth mutant codon of beta globin gene causing polymerization of Haemoglobin and change in RBC shape is ______.
Answer: (A) GUG. Answer: (A) GUG.
- A.GUG✓
- B.AUG
- C.GAG
- D.CAG
Correct Answer
(A) GUG
Solution & Explanation
Answer: (A) GUG. In sickle cell anaemia, a single base-pair change in the beta globin gene alters the sixth codon from GAG (glutamate) to GUG (valine), causing polymerization of haemoglobin and the sickle (changed) RBC shape. NCERT Ch 5, p.97, lines 014-017: "A classical example of point mutation is a change of single base pair in the gene for beta globin chain that results in the change of amino acid residue glutamate to valine. It results into a diseased condition called as sickle cell anemia."
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