The first human hormone produced by recombinant DNA technology is

Options

A. insulin
B. oestrogen
C. thyroxine
D. progesterone

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the first human hormone that was produced using recombinant DNA technology.

2. **Identifying the Options**: The options provided are insulin, estrogen, thyroxine, and progesterone.

3. **Recalling Historical Context**: Insulin is known to be the first human hormone that was successfully produced using recombinant DNA technology in the early 1980s.

4. **Understanding Recombinant DNA Technology**: This technology involves inserting the gene that encodes a specific hormone into a vector, which is then introduced into a host organism (in this case, Escherichia coli).

5. **Production Process**: The gene for insulin consists of two chains (A and B). These chains were isolated and inserted into E. coli. As the bacteria multiply, they produce more copies of these chains.

6. **Final Assembly**: Once the chains are produced, they are isolated and then combined through disulfide bonds to form the active insulin molecule.

7. **Conclusion**: Based on the above steps, the first human hormone produced by recombinant DNA technology is insulin.

**Final Answer**: Insulin

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