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

Options

A. G GG
B. A A G
C. G A A
D. G U G

Answer

To solve the question regarding which triplet codes for valine in the context of sickle cell anemia, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Context of Sickle Cell Anemia**:
- Sickle cell anemia is a genetic disorder caused by a mutation in the hemoglobin gene. Specifically, in the beta chain of hemoglobin, glutamic acid is replaced by valine at the sixth position.

2. **Identify the Codon for Glutamic Acid**:
- The triplet codon that codes for glutamic acid is GAG. This is important as it helps us understand what is being replaced in the mutation.

3. **Identify the Codon for Valine**:
- The triplet codon that codes for valine is GUG. This is the codon we are looking for in the options provided.

4. **Analyze the Given Options**:
- Option 1: GGG
- Option 2: AAG
- Option 3: GAA
- Option 4: GUG

5. **Determine the Correct Answer**:
- Among the options, the triplet that codes for valine is GUG, which corresponds to Option 4.

6. **Conclusion**:
- Therefore, the answer to the question is Option 4: GUG.

### Final Answer:
**The triplet that codes for valine is GUG (Option 4).**