Question

In sickle cell anaemia, glutamic acid is replaced by valine. Which one of the following triplets codes valine?

• A. G A A
• B. A A G
• C. G G G
• D. G U G

Answer 1

The correct option is D

G U G

In sickle cell anaemia, base substitution from glutamic acid to valine occurs at the relevant portion of the beta chain of the haemoglobin molecule. This substitution occurs due to the single base substitution at the sixth codon of the beta globin gene from GAG to GUG.