Which of the following has not been synthesized by DNA technology ?

Options

A. Insulin
B. Haemoglobin
C. Somatostatin
D. Interferon

Answer

To solve the question of which of the following has not been synthesized by DNA technology, we will analyze each option given:

### Step 1: Understand DNA Technology
DNA technology involves the manipulation of an organism's genetic material to produce specific substances. This often includes inserting genes into microorganisms to produce proteins or hormones.

### Step 2: Analyze Each Option
1. **Insulin**:
- Insulin was the first hormone produced using DNA technology. The gene responsible for insulin production was inserted into the bacterium *Escherichia coli* (E. coli), which then produced insulin.
- **Conclusion**: Insulin has been synthesized by DNA technology.

2. **Hemoglobin**:
- Hemoglobin is a protein found in red blood cells that carries oxygen. Unlike insulin, hemoglobin has not been successfully synthesized using DNA technology in a commercially viable way.
- **Conclusion**: Hemoglobin has not been synthesized by DNA technology.

3. **Somatostatin**:
- Somatostatin is another hormone that has been produced using DNA technology. The gene for somatostatin has been inserted into E. coli, leading to its production.
- **Conclusion**: Somatostatin has been synthesized by DNA technology.

4. **Interferon**:
- Interferons are proteins that play a role in the immune response. They have also been produced using DNA technology by inserting the relevant genes into E. coli.
- **Conclusion**: Interferons have been synthesized by DNA technology.

### Step 3: Identify the Correct Answer
Based on the analysis:
- Insulin: Synthesized by DNA technology.
- Hemoglobin: **Not synthesized by DNA technology.**
- Somatostatin: Synthesized by DNA technology.
- Interferon: Synthesized by DNA technology.

Thus, the correct answer is **Hemoglobin** (Option 2).

### Final Answer
**Hemoglobin** has not been synthesized by DNA technology.

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