Which is not true w.r.t transgenic animals and their contribution to human welfare?

Options

A. Transgenic mice are being tested to ensure safety of polio vaciine
B. Rosie's milk contained human gene-insulin
C. Transgenic cows produce milk with less fat
D. Transgenic sheep grow more wool

Answer

To determine which statement is not true regarding transgenic animals and their contributions to human welfare, we can analyze the provided options step by step.

### Step-by-Step Solution:

1. **Understanding Transgenic Animals**:
- Transgenic animals are those that have had foreign genes inserted into their genomes. This genetic modification allows them to express new traits or produce specific proteins that can be beneficial for human use.

2. **Evaluating the Options**:
- **Option 1**: "Transgenic mice are able to be tested to ensure the safety of the polio vaccine."
- This statement is true. Transgenic mice are often used in research to test the safety and efficacy of vaccines, including the polio vaccine.

- **Option 2**: "Rosy milk contains the human gene insulin."
- This statement is false. Rosy milk is produced by transgenic cows that express the human alpha-lactalbumin gene, which increases protein content in milk. Human insulin is produced using genetically modified E. coli, not in rosy milk.

- **Option 3**: "Transgenic cows produce milk with less fat."
- This statement is true. Genetic modifications can be made to reduce the fat content in milk by altering specific genes responsible for fat production.

- **Option 4**: "Transgenic sheep grow more wool."
- This statement is also true. Genetic modifications can enhance wool production in sheep by expressing genes that promote wool growth.

3. **Conclusion**:
- The statement that is not true is **Option 2**: "Rosy milk contains the human gene insulin."

### Final Answer:
The statement that is not true with respect to transgenic animals and their contribution to human welfare is: **"Rosy milk contains the human gene insulin."**

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