Which GMO is now being developed in order to be used in testing the safety of polio vaccines before to be used in human ?

Options

A. Transgenic sheep
B. Transgenic cow
C. Transgenic mice
D. Transgenic viruses

Answer

**Step-by-Step Solution:**

1. **Understanding GMO**: The question asks about a genetically modified organism (GMO) that is being developed for testing the safety of polio vaccines. A GMO is an organism whose genetic material has been altered using genetic engineering techniques.

2. **Identifying Options**: The options provided include various transgenic organisms: transgenic sheep, transgenic cows, transgenic mice, and transgenic viruses. We need to evaluate which of these is specifically being developed for testing polio vaccine safety.

3. **Evaluating Each Option**:
- **Transgenic Sheep**: These are typically developed for producing milk with specific proteins. They are not primarily used for vaccine testing.
- **Transgenic Cows**: Similar to sheep, these cows are modified to produce milk rich in certain proteins but are not used for testing vaccines.
- **Transgenic Mice**: These mice have altered genomes and are widely used in research, including testing the safety and efficacy of vaccines. They can provide valuable insights into how a vaccine might perform in humans.
- **Transgenic Viruses**: While these are used in recombinant DNA technology, they are not specifically developed for testing vaccine safety.

4. **Conclusion**: Based on the evaluation, the correct answer is **transgenic mice**. They are being developed and utilized to test the safety of polio vaccines before they are administered to humans.

**Final Answer**: Transgenic mice are being developed for testing the safety of polio vaccines before they are used in humans.

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