Which of the following is not true regarding the transgenic animals ?

Options

A. Transgenic mice are being developed for use in testing the safety of vaccines before they are used on humans.
B. They are used to study complex factors involved in growth such as insulin-like growth factor .
C. Protein alpha - 1 antitrypsin is used for replacement therapy for individuals at risk from emphysema.
D. In `1997,` the first transgenic cow, Rosie, produced human protein beta lactalbumin enriched milk

Answer

To solve the question regarding which statement is not true about transgenic animals, we will analyze each option provided.

### Step-by-Step Solution:

1. **Analyze the First Statement**:
- **Statement**: "Transgenic mice are being developed for use in testing the safety of vaccines before they are used on humans."
- **Evaluation**: This statement is true. Transgenic mice are indeed used in research to test the safety and efficacy of vaccines before they are administered to humans.

2. **Analyze the Second Statement**:
- **Statement**: "They are used to study complex factors involved in growth such as insulin-like growth factor."
- **Evaluation**: This statement is also true. Transgenic animals are used to study various biological processes, including the role of insulin-like growth factors in growth and metabolism.

3. **Analyze the Third Statement**:
- **Statement**: "Protein alpha 1 antitrypsin is used for replacement therapy for individuals that are at risk for emphysema."
- **Evaluation**: This statement is true. Alpha 1 antitrypsin is indeed used in augmentation therapy for patients with emphysema, providing a necessary protein that they lack.

4. **Analyze the Fourth Statement**:
- **Statement**: "In 1997, the first transgenic cow, Rosy, produced human protein beta-lactalbumin enriched milk."
- **Evaluation**: This statement is false. The transgenic cow named Rosy produced milk enriched with alpha-lactalbumin, not beta-lactalbumin. Therefore, this statement is not true regarding transgenic animals.

### Conclusion:
The statement that is not true regarding transgenic animals is: "In 1997, the first transgenic cow, Rosy, produced human protein beta-lactalbumin enriched milk."

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