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

Options

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

Explanation

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 beta-globin gene of hemoglobin. This mutation results in the substitution of one amino acid for another in the hemoglobin protein.

2. **Identify the Amino Acid Change**:
- In sickle cell anemia, glutamic acid (which is coded by the codon GAG) is replaced by valine (which is coded by the codon GUG).

3. **Analyze the Given Triplets**:
- The options provided are:
- GGG
- AAG
- GAA
- GUG

4. **Determine the Corresponding Amino Acids for Each Triplet**:
- GGG codes for Glycine.
- AAG codes for Lysine.
- GAA codes for Glutamic Acid.
- GUG codes for Valine.

5. **Select the Correct Triplet**:
- From the analysis, the triplet that codes for valine is GUG.

### Final Answer:
- The triplet that codes for valine is **GUG**.

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